Solid-state imaging device and electronic apparatus

ABSTRACT

The present technology relates to a solid-state imaging device and an electronic apparatus that enable simultaneous acquisition of a signal for generating a high dynamic range image and a signal for detecting a phase difference.The solid-state imaging device includes a plurality of pixel sets each including color filters of the same color, for a plurality of colors, each pixel set including a plurality of pixels. Each pixel includes a plurality of photodiodes PD. The present technology can be applied, for example, to a solid-state imaging device that generates a high dynamic range image and detects a phase difference, and the like.

CROSS REFERENCES TO RELATED APPLICATIONS

The present Application is a Continuation Application of U.S. patentapplication Ser. No. 16/764,474 filed May 15, 2020, which is a 371National Stage Entry of International Application No.:PCT/JP2018/041820, filed on Nov. 12, 2018, which in turn claims priorityfrom Japanese Application No. 2017-224138, filed on Nov. 22, 2017, theentire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present technology relates to a solid-state imaging device and anelectronic apparatus, and more particularly, relates to a solid-stateimaging device and an electronic apparatus configured to be able tosimultaneously acquire a signal for generating a high dynamic rangeimage and a signal for detecting a phase difference.

BACKGROUND ART

There has been proposed a solid-state imaging device that achievessimultaneous acquisition of two types of pixel signals, ahigh-sensitivity signal and a low-sensitivity signal, for generating ahigh dynamic range image (hereinafter also referred to as an HDR image)and acquisition of a phase difference detection signal for distancemeasurement (see, for example, Patent Document 1).

CITATION LIST Patent Document

Patent Document 1: Japanese Patent Application Laid-Open No. 2016-171308

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

In a pixel structure of Patent Document 1, three photodiodes are formedunder one on-chip lens. If the curvature of the on-chip lens isincreased to increase the refractive power to improve the angledependence for specialization in phase difference characteristics, itbecomes difficult to generate HDR images. Conversely, if the curvatureof the on-chip lens is reduced to reduce the refractive power to reducethe angle dependence for specialization in favorable generation of HDRimages, the degree of separation of phase difference characteristics isdeteriorated. Thus, it is difficult to achieve both phase differencecharacteristics and HDR characteristics. There has also been proposed alens structure in which the curvature of one on-chip lens is changed,but it is sensitive to variation in shape, and thus is difficult toproduce in large quantities.

The present technology has been made in view of such a situation, and isintended to enable simultaneous acquisition of a signal for generating ahigh dynamic range image and a signal for detecting a phase difference.

Solutions to Problems

A solid-state imaging device according to a first aspect of the presenttechnology includes a plurality of pixel sets each including colorfilters of the same color, for a plurality of colors, each pixel setincluding a plurality of pixels, each pixel including a plurality ofphotoelectric conversion parts.

An electronic apparatus according to a second aspect of the presenttechnology includes a solid-state imaging device including a pluralityof pixel sets each including color filters of the same color, for aplurality of colors, each pixel set including a plurality of pixels,each pixel including a plurality of photoelectric conversion parts.

In the first and second aspects of the present technology, a pluralityof pixel sets each including color filters of the same color is providedfor a plurality of colors, each pixel set is provided with a pluralityof pixels, and each pixel is provided with a plurality of photoelectricconversion parts.

The solid-state imaging device and the electronic apparatus may beindependent devices, or may be modules incorporated into other devices.

Effects of the Invention

According to the first and second aspects of the present technology, itis possible to simultaneously acquire a signal for generating a highdynamic range image and a signal for detecting a phase difference.

Note that the effects described here are not necessarily limiting, andany effect described in the present disclosure may be included.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating a schematic configuration of asolid-state imaging device to which the present technology is applied.

FIG. 2 is a diagram illustrating a first cross-sectional configurationexample of a pixel array of the solid-state imaging device in FIG. 1.

FIG. 3 is a diagram illustrating a color array of color filters.

FIG. 4 is a diagram illustrating a circuit configuration of a pixel set.

FIG. 5 is a diagram illustrating a configuration of signal lines thatcontrol transfer transistors of pixel sets.

FIG. 6 is a diagram illustrating drive in a case where the solid-stateimaging device operates in a full-resolution mode.

FIG. 7 is a diagram illustrating a modification of the full-resolutionmode.

FIG. 8 is a diagram illustrating drive in a case where the solid-stateimaging device operates in a four-pixel addition phase-differencedetection mode.

FIG. 9 is a diagram illustrating drive in a case where the solid-stateimaging device operates in a first phase difference HDR mode.

FIG. 10 is a diagram illustrating a procedure of reading pixel signalsin the first phase difference HDR mode.

FIG. 11 is a diagram illustrating drive in a case where the solid-stateimaging device operates in a second phase difference HDR mode.

FIG. 12 is a diagram illustrating a procedure of reading pixel signalsin the second phase difference HDR mode.

FIG. 13 is a diagram illustrating a wiring example of signal linesspecialized for the first phase difference HDR mode.

FIG. 14 is a diagram illustrating a wiring example of signal linesspecialized for the second phase difference HDR mode.

FIG. 15 is a diagram illustrating a modification of the color array ofthe color filters.

FIG. 16 is a diagram illustrating a modification of orientations ofphotodiodes PD.

FIG. 17 is a diagram illustrating a modification of arrangement ofon-chip lenses.

FIG. 18 is a diagram illustrating a second cross-sectional configurationexample of the pixel array of the solid-state imaging device in FIG. 1.

FIG. 19 is a plan view illustrating regions where an insulating layer inFIG. 18 is formed.

FIG. 20 is a diagram illustrating a third cross-sectional configurationexample of the pixel array of the solid-state imaging device in FIG. 1.

FIG. 21 is a plan view illustrating regions where an insulating layerand an impurity layer in FIG. 18 are formed.

FIG. 22 is a diagram illustrating the potential of the impurity layer inFIG. 21.

FIG. 23 is a diagram illustrating a modification of the thirdcross-sectional configuration example in FIG. 20.

FIG. 24 is a plan view illustrating a first configuration in which alight-shielding film is disposed on photodiodes PD.

FIG. 25 is a plan view illustrating a second configuration in which thelight-shielding film is disposed on photodiodes PD.

FIG. 26 is a plan view illustrating a third configuration in which thelight-shielding film is disposed on photodiodes PD.

FIG. 27 is a plan view illustrating a fourth configuration in which thelight-shielding film is disposed on photodiodes PD.

FIG. 28 is a diagram illustrating another modification of thesolid-state imaging device in FIG. 1.

FIG. 29 is a diagram illustrating still another modification of thesolid-state imaging device in FIG. 1.

FIG. 30 is a plan view illustrating an example of arrangement of pixeltransistors.

FIG. 31 is a block diagram illustrating a configuration example of animaging apparatus as an electronic apparatus to which the presenttechnology is applied.

FIG. 32 is a diagram illustrating an example of use of an image sensor.

FIG. 33 is a diagram illustrating an example of a schematicconfiguration of an endoscopic surgery system.

FIG. 34 is a block diagram illustrating an example of a functionalconfiguration of a camera head and a CCU.

FIG. 35 is a block diagram illustrating an example of a schematicconfiguration of a vehicle control system.

FIG. 36 is an explanatory diagram illustrating an example ofinstallation positions of a vehicle exterior information detection unitand imaging units.

MODE FOR CARRYING OUT THE INVENTION

Hereinafter, a mode for carrying out the present technology (hereinafterreferred to as an embodiment) will be described. Note that thedescription will be made in the following order.

1. Schematic configuration example of solid-state imaging device

2. First cross-sectional configuration example of pixels

3. Example of arrangement of color filters

4. Circuit configuration example of pixel set

5. Explanation of output modes

6. Modification of color array of color filters

7. Modification of orientations of photodiodes

8. Modification of on-chip lens arrangement

9. Second cross-sectional configuration example of pixels

10. Third cross-sectional configuration example of pixels

11. Configuration example in which light-shielding film is added

12. Other modifications

13. Pixel transistor arrangement example

14. Example of application to electronic apparatus

15. Example of application to endoscopic surgery system

16. Example of application to mobile object

<1. Schematic Configuration Example of Solid-State Imaging Device>

FIG. 1 illustrates a schematic configuration of a solid-state imagingdevice to which the present technology is applied.

A solid-state imaging device 1 of FIG. 1 includes a pixel array 3 withpixels 2 two-dimensionally arrayed in a matrix, and peripheral circuitryaround the pixel array 3 on a semiconductor substrate 12 using, forexample, silicon (Si) as a semiconductor. The peripheral circuitryincludes a vertical drive circuit 4, column signal processing circuits5, a horizontal drive circuit 6, an output circuit 7, a control circuit8, and others.

The pixels 2 each include photodiodes as photoelectric conversion partsand a plurality of pixel transistors. Note that, as described later withreference to FIG. 4, the pixels 2 are formed in a shared pixel structurein which floating diffusion as a charge holding part that holds chargesgenerated in the photodiodes is shared among a plurality of pixels 2. Inthe shared pixel structure, photodiodes and transfer transistors areprovided for each pixel, and a selection transistor, a reset transistor,and an amplification transistor are shared by a plurality of pixels.

The control circuit 8 receives an input clock and data instructing anoperation mode or the like, and outputs data such as internalinformation of the solid-state imaging device 1. Specifically, on thebasis of a vertical synchronization signal, a horizontal synchronizationsignal, and a master clock, the control circuit 8 generates a clocksignal and a control signal on the basis of which the vertical drivecircuit 4, the column signal processing circuits 5, the horizontal drivecircuit 6, and others operate. Then, the control circuit 8 outputs thegenerated clock signal and control signal to the vertical drive circuit4, the column signal processing circuits 5, the horizontal drive circuit6, and others.

The vertical drive circuit 4 is formed, for example, by a shiftregister, and selects a predetermined pixel drive wire 10, provides apulse for driving the pixels 2 to the selected pixel drive wire 10, anddrives the pixels 2 row by row. That is, the vertical drive circuit 4performs control to selectively scan the pixels 2 of the pixel array 3in the vertical direction sequentially row by row, and output pixelsignals based on signal charges generated in the photoelectricconversion parts of the pixels 2 depending on the amount of receivedlight, through vertical signal lines 9 to the column signal processingcircuits 5.

The column signal processing circuits 5 are arranged for thecorresponding columns of the pixels 2, and perform signal processingsuch as noise removal on signals output from the pixels 2 in one row forthe corresponding pixel columns. For example, the column signalprocessing circuits 5 perform signal processing such as correlateddouble sampling (CDS) for removing fixed pattern noise peculiar topixels and AD conversion.

The horizontal drive circuit 6 is formed, for example, by a shiftregister, selects each of the column signal processing circuits 5 inorder by sequentially outputting a horizontal scanning pulse, and causeseach of the column signal processing circuits 5 to output a pixel signalto a horizontal signal line 11.

The output circuit 7 performs predetermined signal processing on asignal sequentially provided from each of the column signal processingcircuits 5 through the horizontal signal line 11, and outputs thesignal. For example, the output circuit 7 may perform only buffering, ormay perform various types of digital signal processing such as blacklevel adjustment and column variation correction. An input-outputterminal 13 exchanges signals with the outside.

The solid-state imaging device 1 formed as described above is a CMOSimage sensor called a column AD system in which the column signalprocessing circuits 5 that perform CDS processing and AD conversionprocessing are arranged for the corresponding pixel columns.

Furthermore, the solid-state imaging device 1 may be formed by a chip ofa stacked structure in which a plurality of substrates is stacked. Achip with a plurality of substrates stacked is formed by stacking alower substrate and an upper substrate in that order from below upward.At least one or more of the control circuit 8, the vertical drivecircuit 4, the column signal processing circuits 5, the horizontal drivecircuit 6, and the output circuit 7 are formed on the lower substrate,and at least the pixel array 3 is formed on the upper substrate.Connection portions connect the vertical drive circuit 4 to the pixelarray 3, and the column signal processing circuits 5 to the pixel array3, so that signals are transmitted between the lower substrate and theupper substrate. The connection portions are formed, for example, bythrough silicon vias (TSVs), Cu—Cu, or the like.

<2. First Cross-Sectional Configuration Example of Pixels>

FIG. 2 is a diagram illustrating a first cross-sectional configurationexample of the pixel array 3 of the solid-state imaging device 1 in FIG.1.

In the pixel array 3 of the solid-state imaging device 1, photodiodes PDare formed by, for example, forming N-type (second conductivity type)semiconductor regions 32 in a P-type (first conductivity type)semiconductor region 31 in the semiconductor substrate 12. In each pixel2 of the pixel array 3, two photodiodes PD are formed per pixel, and thetwo photodiodes PD are formed in such a manner as to be symmetricallydisposed in two parts into which a pixel region is divided equally. Notethat in the following description, of the two photodiodes PD formed inone pixel, the photodiode PD disposed on the right side in the figure issometimes referred to as the right photodiode PD, and the photodiode PDdisposed on the left side as the left photodiode PD.

On the front side of the semiconductor substrate 12 that is the lowerside in FIG. 2, a multilayer wiring layer 35 is formed which includespixel transistors (not illustrated) for performing reading of chargesgenerated and accumulated in the photodiodes PD of each pixel 2 and thelike, a plurality of wiring layers 33, and an interlayer dielectric 34.

On the other hand, on pixel boundary portions on the back side of thesemiconductor substrate 12 that is the upper side in FIG. 2, aninter-pixel light-shielding film 36 is formed. The inter-pixellight-shielding film 36 may be of any material that blocks light, and isdesirably of a material that has a high light-blocking property and canbe processed with high precision by fine processing such as etching. Theinter-pixel light-shielding film 36 can be formed, for example, by ametal film of tungsten (W), aluminum (Al), copper (Cu), titanium (Ti),molybdenum (Mo), nickel (Ni), or the like.

In addition, for example, an antireflection film (insulating layer)formed, for example, by a silicon oxide film or the like may be furtherformed on a back side interface of the semiconductor substrate 12.

On the back surface of the semiconductor substrate 12 including theinter-pixel light-shielding film 36, color filters 37 are formed. Thecolor filters 37 are formed by spin-coating photosensitive resincontaining coloring matters such as pigments or dyes, for example. Thecolor array of the color filters 37 will be described later withreference to FIG. 3. Red (R), green (G), and blue (B) colors arearranged in a Bayer array in units of four pixels in 2×2 (two rows bytwo columns).

On the color filters 37, on-chip lenses 38 are formed for the individualpixels. The on-chip lenses 38 are formed, for example, of a resinmaterial such as a styrene resin, an acrylic resin, a styrene-acrylcopolymer resin, or a siloxane resin.

As described above, the solid-state imaging device 1 is a back-sideilluminated CMOS solid-state imaging device in which the color filters37 and the on-chip lenses 38 are formed on the back side of thesemiconductor substrate 12 opposite to the front side on which themultilayer wiring layer 35 is formed, so that light enters from the backside.

Each pixel 2 of the solid-state imaging device 1 has two separatephotodiodes PD in the pixel. The two photodiodes PD are formed atdifferent positions, so that a shift occurs between images generatedfrom the two photodiodes PD, individually. From this image shift, theamount of phase shift is calculated to calculate the amount of defocus.By adjusting (moving) an imaging lens, autofocus can be achieved.

<3. Example of Arrangement of Color Filters>

Next, with reference to FIG. 3, the color array of the color filters 37in the pixel array 3 will be described.

In the pixel array 3 with the pixels 2 two-dimensionally arrayed in amatrix, four pixels 2 in 2×2 (two vertical pixels×two horizontal pixels)constitute one pixel set 51. And the color filters 37 are arranged to beof the same color in each individual pixel set 51. More specifically,the R, G, and B color filters 37 are arranged in a Bayer array in unitsof the pixel sets 51.

In FIG. 3, the pixel set 51 having the R color filters 37 is representedby a pixel set 51R, and the pixel set 51 having the G color filters 37adjacent to the pixel set 51R is represented by a pixel set 51Gr.Furthermore, the pixel set 51 having the B color filters 37 isrepresented by a pixel set 51B, and the pixel set 51 having the G colorfilters 37 adjacent to the pixel set 51B is represented by a pixel set51Gb. Note that the configuration of the color filters is not limited toRGB primary-colors filters, and various configurations including filtersof complementary colors such as cyan, magenta, yellow, and green (CMYG)may be applied.

Furthermore, the orientations of the longitudinal shape of the twophotodiodes PD formed in each pixel 2 are the same direction in thepixel set 51, and also, they are formed in the same direction in all thepixel sets 51.

The on-chip lenses 38 are formed for the individual pixels.

<4. Circuit Configuration Example of Pixel Set>

Next, FIG. 4 is a diagram illustrating a circuit configuration of thepixel set 51.

FIG. 4 illustrates a circuit configuration of the pixel set 51Gr as anexample of the pixel set 51.

Each pixel 2 of the pixel set 51Gr includes two photodiodes PD and twotransfer transistors TG for transferring charges accumulated in them.And one FD 52, one reset transistor 53, one amplification transistor 54,and one selection transistor 55 are provided for the pixel set 51Gr.Each of the reset transistor 53, the amplification transistor 54, andthe selection transistor 55 is shared by the four pixels of the pixelset 51Gr. The four pixels sharing the reset transistor 53, theamplification transistor 54, and the selection transistor 5 form asharing unit.

Note that in the following, in a case where the two photodiodes PD andthe two transfer transistors TG of each pixel 2 in the pixel set 51Grare distinguished from each other, of the four pixels in 2×2constituting the pixel set 51Gr, the two photodiodes PD of the upperleft pixel 2 are referred to as photodiodes PD_Gr1L and PD_Gr1R, and thetwo transfer transistors TG that transfer charges accumulated in thephotodiodes PD_Gr1L and PD_Gr1R are referred to as transfer transistorsTG_Gr1L and TG_Gr1R.

Furthermore, the two photodiodes PD of the upper right pixel 2 arereferred to as photodiodes PD_Gr2L and PD_Gr2R, and the two transfertransistors TG that transfer charges accumulated in the photodiodesPD_Gr2L and PD_Gr2R are referred to as transfer transistors TG_Gr2L andTG_Gr2R.

Likewise, the two photodiodes PD of the lower left pixel 2 are referredto as photodiodes PD_Gr3L and PD_Gr3R, and the two transfer transistorsTG that transfer charges accumulated in the photodiodes Gr3L and Gr3Rare referred to as transfer transistors TG_Gr3L and TG_Gr3R. The twophotodiodes PD of the lower right pixel 2 are referred to as photodiodesPD_Gr4L and PD_Gr4R, and the two transfer transistors TG that transfercharges accumulated in the photodiodes PD_Gr4L and PD_Gr4R are referredto as transfer transistors TG_Gr4L and TG_Gr4R.

Each of the photodiodes PD of each pixel 2 in the pixel set 51Grreceives light and generates and accumulates photocharges.

When a drive signal TRGGr1L provided to the gate electrode becomesactive, the transfer transistor TG_Gr1L becomes conductive in responseto this, transferring photocharges accumulated in the photodiode PD_Gr1Lto the FD 52. When a drive signal TRGGr1R provided to the gate electrodebecomes active, the transfer transistor TG_Gr1R becomes conductive inresponse to this, transferring photocharges accumulated in thephotodiode PD_Gr1R to the FD 52.

When a drive signal TRGGr2L provided to the gate electrode becomesactive, the transfer transistor TG_Gr2L becomes conductive in responseto this, transferring photocharges accumulated in the photodiode PD_Gr2Lto the FD 52. When a drive signal TRGGr2R provided to the gate electrodebecomes active, the transfer transistor TG_Gr2R becomes conductive inresponse to this, transferring photocharges accumulated in thephotodiode PD_Gr2R to the FD 52. The similar applies to the photodiodesPD_Gr3L, PD_Gr3R, PD_Gr4L, and PD_Gr4R, and the transfer transistorsTG_Gr3L, TG_Gr3R, TG_Gr4L, and TG_Gr4R.

The FD 52 temporarily holds photocharges provided from each photodiodePD of each pixel 2 in the pixel set 51Gr.

When a drive signal RST provided to the gate electrode becomes active,the reset transistor 53 becomes conductive in response to this,resetting the potential of the FD 52 to a predetermined level (resetvoltage VDD).

The amplification transistor 54 has a source electrode connected to thevertical signal line 9 via the selection transistor 55, thereby forminga source follower circuit with a load MOS of a constant current sourcecircuit 56 connected to one end of the vertical signal line 9.

The selection transistor 55 is connected between the source electrode ofthe amplification transistor 54 and the vertical signal line 9. When aselection signal SEL provided to the gate electrode becomes active, theselection transistor 55 becomes conductive in response to this, bringingthe sharing unit into a selected state and outputting pixel signals ofthe pixels 2 in the sharing unit output from the amplificationtransistor 54 to the vertical signal line 9. Note that for the pixel set51 (the pixel set 51Gr in FIG. 4), one selection transistor 55 may beprovided as illustrated in FIG. 4, or two or more selection transistors55 may be provided. In a case where two or more selection transistors 55are provided for the pixel set 51, the two or more selection transistors55 are connected to different vertical signal lines 9, so that pixelsignals can be read at higher speed.

The transfer transistors TG of the pixels 2, the reset transistor 53,the amplification transistor 54, and the selection transistor 55 arecontrolled by the vertical drive circuit 4.

FIG. 5 illustrates a configuration of signal lines for providing thedrive signals TRGGr to the gate electrodes of the eight transfertransistors TG constituting the pixel set 51 as illustrated in FIG. 4.

In order to provide the drive signals TRGGr to the gate electrodes ofthe eight transfer transistors TG constituting the pixel set 51Gr, asillustrated in FIG. 5, eight signal lines 61-1 to 61-8 are required fora plurality of pixel sets 51 arrayed in the horizontal direction. Theeight signal lines 61-1 to 61-8 are part of the pixel drive wires 10 inFIG. 1.

The signal line 61-1 transmits the drive signal TRGGr1L to be providedto the gate electrode of the transfer transistor TG_Gr1L in the pixelset 51Gr. Furthermore, the signal line 61-1 also transmits the drivesignal TRGGr1L to the gate electrode of a transfer transistor TG_R1L(not illustrated) in the pixel set 51R adjacent to the pixel set 51Gr,located at the same position as the transfer transistor TG_Gr1L in thepixel set 51Gr.

The signal line 61-2 transmits the drive signal TRGGr1R to be providedto the gate electrode of the transfer transistor TG_Gr1R in the pixelset 51Gr. Furthermore, the signal line 61-2 also transmits the drivesignal TRGGr1R to the gate electrode of a transfer transistor TG_R1R(not illustrated) in the pixel set 51R adjacent to the pixel set 51Gr,located at the same position as the transfer transistor TG_Gr1R in thepixel set 51Gr.

The signal line 61-3 transmits the drive signal TRGGr2L to be providedto the gate electrode of the transfer transistor TG_Gr2L in the pixelset 51Gr. Furthermore, the signal line 61-3 also transmits the drivesignal TRGGr2L to the gate electrode of a transfer transistor TG_R2L(not illustrated) in the pixel set 51R adjacent to the pixel set 51Gr,located at the same position as the transfer transistor G_Gr2L in thepixel set 51Gr.

The signal line 61-4 transmits the drive signal TRGGr2R to be providedto the gate electrode of the transfer transistor TG_Gr2R in the pixelset 51Gr. Furthermore, the signal line 61-4 also transmits the drivesignal TRGGr2R to the gate electrode of a transfer transistor TG_R2R(not illustrated) in the pixel set 51R adjacent to the pixel set 51Gr,located at the same position as the transfer transistor TG_Gr2R in thepixel set 51Gr.

The signal line 61-5 transmits the drive signal TRGGr3L to be providedto the gate electrode of the transfer transistor TG_Gr3L in the pixelset 51Gr. Furthermore, the signal line 61-5 also transmits the drivesignal TRGGr3L to the gate electrode of a transfer transistor TG_R3L(not illustrated) in the pixel set 51R adjacent to the pixel set 51Gr,located at the same position as the transfer transistor TG_Gr3L in thepixel set 51Gr.

The signal line 61-6 transmits the drive signal TRGGr3R to be providedto the gate electrode of the transfer transistor TG_Gr3R in the pixelset 51Gr. Furthermore, the signal line 61-6 also transmits the drivesignal TRGGr3R to the gate electrode of a transfer transistor TG_R3R(not illustrated) in the pixel set 51R adjacent to the pixel set 51Gr,located at the same position as the transfer transistor TG_Gr3R in thepixel set 51Gr.

The signal line 61-7 transmits the drive signal TRGGr4L to be providedto the gate electrode of the transfer transistor TG_Gr4L in the pixelset 51Gr. Furthermore, the signal line 61-7 also transmits the drivesignal TRGGr4L to the gate electrode of a transfer transistor TG_R4L(not illustrated) in the pixel set 51R adjacent to the pixel set 51Gr,located at the same position as the transfer transistor TG_Gr4L in thepixel set 51Gr.

The signal line 61-8 transmits the drive signal TRGGr4R to be providedto the gate electrode of the transfer transistor TG_Gr4R in the pixelset 51Gr. Furthermore, the signal line 61-8 also transmits the drivesignal TRGGr4R to the gate electrode of a transfer transistor TG_R4R(not illustrated) in the pixel set 51R adjacent to the pixel set 51Gr,located at the same position as the transfer transistor TG_Gr4R in thepixel set 51Gr.

Likewise, eight signal lines 62-1 to 62-8 are required for the pixelsets 51B and 51Gb arrayed in the horizontal direction.

The signal line 62-1 transmits a drive signal TRGGb1L to the gateelectrodes of transfer transistors TG in the pixel sets 51B and 51Gbcorresponding to the transfer transistor TG_Gr1L in the pixel set 51Gr.

The signal line 62-2 transmits a drive signal TRGGb1R to the gateelectrodes of transfer transistors TG in the pixel sets 51B and 51Gbcorresponding to the transfer transistor TG_Gr1R in the pixel set 51Gr.

The signal line 62-3 transmits a drive signal TRGGb2L to the gateelectrodes of transfer transistors TG in the pixel sets 51B and 51Gbcorresponding to the transfer transistor TG_Gr2L in the pixel set 51Gr.

The signal line 62-4 transmits a drive signal TRGGb2R to the gateelectrodes of transfer transistors TG in the pixel sets 51B and 51Gbcorresponding to the transfer transistor TG_Gr2R in the pixel set 51Gr.

The signal line 62-5 transmits a drive signal TRGGb3L to the gateelectrodes of transfer transistors TG in the pixel sets 51B and 51Gbcorresponding to the transfer transistor TG_Gr3L in the pixel set 51Gr.

The signal line 62-6 transmits a drive signal TRGGb3R to the gateelectrodes of transfer transistors TG in the pixel sets 51B and 51Gbcorresponding to the transfer transistor TG_Gr3R in the pixel set 51Gr.

The signal line 62-7 transmits a drive signal TRGGb4L to the gateelectrodes of transfer transistors TG in the pixel sets 51B and 51Gbcorresponding to the transfer transistors TG_Gr4L in the pixel set 51Gr.

The signal line 62-8 transmits a drive signal TRGGb4R to the gateelectrodes of transfer transistors TG in the pixel sets 51B and 51Gbcorresponding to the transfer transistor TG_Gr4R in the pixel set 51Gr.

By forming the circuit of the plurality of pixels 2 in the sharing unitas above, the pixels 2 in the sharing unit can output a pixel signal foreach photodiode PD as a unit, and can output a pixel signal for eachpixel as a unit or for a plurality of pixels as a unit, in response to adrive signal from the vertical drive circuit 4. In a case where a pixelsignal is output for each pixel as a unit or for a plurality of pixelsas a unit, a plurality of transfer transistors TG that outputssimultaneously is activated simultaneously. The FD 52 adds chargesprovided from a plurality of photodiodes PD via the transfer transistorsTG simultaneously activated. Consequently, a pixel signal of each pixelas a unit or of a plurality of pixels as a unit is output from the FD 52through the amplification transistor 54 and the selection transistor 55to the column signal processing circuit 5.

Note that although FIGS. 4 and 5 illustrate a circuit example in whichthe four pixels in 2×2 constituting the pixel set 51 are a sharing unit,the combination of a plurality of pixels as a sharing unit is notlimited to this. For example, two pixels in 1×2 (one vertical pixel×twohorizontal pixels) or in 2×1 (two vertical pixels×one horizontal pixel)may be a sharing unit, or four pixels in 4×1 (four vertical pixels×onehorizontal pixel) may be a sharing unit.

<5. Explanation of Output Mode>

<5.1 Full-Resolution Mode>

Next, a plurality of output modes that can be executed by thesolid-state imaging device 1 will be described.

First, a full-resolution mode in which pixel signals generated in allthe photodiodes PD in the pixel array 3 are output individually will bedescribed.

FIG. 6 is a diagram illustrating drive (pixel signal output control) ofthe pixel set 51Gr in a case where the solid-state imaging device 1operates in the full-resolution mode.

A photodiode PD hatched in FIG. 6 represents a photodiode PD selected tooutput a pixel signal. In the full-resolution mode, as illustrated inFIG. 6, the eight photodiodes PD in the pixel set 51Gr are selectedsequentially, and pixel signals generated individually by the eightphotodiodes PD are output individually.

In the example of FIG. 6, the order in which the eight photodiodes PDare selected is the order of the photodiodes PD_Gr1L, PD_Gr1R, PD_Gr2L,PD_Gr2R, PD_Gr3L, PD_Gr3R, PD_Gr4L, and PD_Gr4R. The order is notlimited to this.

In the full-resolution mode, by combining pixel signals of the twophotodiodes PD in the same pixel, a pixel signal of one pixel can beobtained, and by comparing the pixel signals of the two photodiodes PDin the same pixel, a phase difference can be detected. The other pixelsets 51Gb, 51R, and 51B perform an operation similar to that of thepixel set 51Gr in FIG. 6.

Thus, in the full-resolution mode, all the pixels 2 can output a signalof each pixel as a unit and output signals for detecting a phasedifference.

Furthermore, in the solid-state imaging device 1, the color filters 37of R, G, or B are arranged in units of four pixels (in units of thepixel sets 51) as illustrated in FIG. 3, but the full-resolution modealso allows re-mosaicing processing to regenerate and output pixelsignals in a Bayer array of R, G, B in units of pixels.

Note that in the full-resolution mode in which the drive in FIG. 6 isperformed, the frame rate is reduced and the power consumption isincreased. Thus, drive without performing phase difference detection onsome of the pixels 2 in the pixel set 51Gr may be performed.

For example, as illustrated in FIG. 7, for the upper right pixel 2 andthe lower left pixel 2 of the four pixels constituting the pixel set51Gr, the solid-state imaging device 1 drives the two photodiodes PD inthe pixels to read them simultaneously. Also in FIG. 7, a hatchedphotodiode PD represents a photodiode PD selected to output a pixelsignal.

Phase difference is detected using pixel signals of the photodiodesPD_Gr1L and PD_Gr1R of the upper left pixel 2 and the photodiodesPD_Gr4L and PD_Gr4R of the lower right pixel 2. Thus, by reducing thenumber of pixels 2 in which a phase difference is detected, the framerate and the power consumption can be improved. Alternatively, pixels 2in which a phase difference can be detected may be changed depending ondifference in the amount of light received. For example, in lowillumination, the drive in FIG. 6 is performed in which phase differencedetection is performed in all the pixels, and in high illumination, thedrive in FIG. 7 is performed in which some of the pixels 2 are excluded.

The example of FIG. 7 is an example in which phase difference detectionis performed in two pixels of the four pixels constituting the pixel set51Gr, but drive to perform phase difference detection in only one pixelmay be performed.

<5.2 Four-Pixel Addition Phase-Difference Detection Mode>

Next, a four-pixel addition phase-difference detection mode will bedescribed.

The solid-state imaging device 1 can execute the four-pixel additionphase-difference detection mode in which pixel signals are added andoutput in each pixel set 51 that is a sharing unit, that is, in units offour pixels in 2×2, and a phase difference is detected on the entiresurface of the pixel array 3.

FIG. 8 is a diagram illustrating drive in the four-pixel additionphase-difference detection mode.

Also in FIG. 8, a hatched photodiode PD represents a photodiode PDselected to output a pixel signal.

In the four-pixel addition phase-difference detection mode, thesolid-state imaging device 1 adds and outputs pixel signals ofphotodiodes PD located at the same position in the pixels of the pixelset 51, of the pairs of photodiodes PD of the pixels 2. For example, asillustrated in A of FIG. 8, the solid-state imaging device 1 first addsand outputs pixel signals of all the left photodiodes PD in the pixelset 51, and then, as illustrated in B of FIG. 8, adds and outputs pixelsignals of all the right photodiodes PD in the pixel set 51. Note thatthe reading order of the left photodiodes PD and the right photodiodesPD may be reversed.

By performing such drive, a phase difference can be detected from apixel signal of the left photodiodes PD and a pixel signal of the rightphotodiodes PD in each individual pixel set 51 read, and by combiningthe two pixel signals, a pixel signal output of each individual pixelset 51 (a unit of four pixels) can be obtained. In other words, anentire-surface phase difference can be detected while the advantage of adynamic range due to increased pixel capacitance Qs is maintained.

As a method of discernibly reading a pixel signal of left photodiodes PDand a pixel signal of right photodiodes PD, two ways can be adopted: afirst reading method of separately reading a pixel signal of leftphotodiodes PD and a pixel signal of right photodiodes PD, and a secondreading method of reading a signal obtained by adding a pixel signal ofleft photodiodes PD and a pixel signal of right photodiodes PD.

The first reading method and the second reading method will be brieflydescribed.

First, the first reading method will be described.

First, while left and right photodiodes PD are receiving light(exposed), a dark level signal for performing correlated double samplingis acquired.

After the elapse of a predetermined exposure time, the solid-stateimaging device 1 first reads a pixel signal of one of left and rightphotodiode PD groups of the pixel set 51, for example, a pixel signal ofthe left photodiode PD group.

For example, the reading of a pixel signal of the left photodiode PDgroup will be described with the example of the pixel set 51Grillustrated in FIG. 4. After the selection transistor 55 is activated,the transfer transistors TG_Gr1L, TG_Gr2L, TG_Gr3L, and TG_Gr4L areactivated to transfer charges accumulated in the photodiodes PD_Gr1L,PD_Gr2L, PD_Gr3L, and PD_Gr4L to the FD 52, so that a voltage signalcorresponding to the accumulated charges in the FD 52 is output throughthe vertical signal line 9 to the column signal processing circuit 5.

The voltage signal output to the column signal processing circuit 5 isthe sum of the pixel signal of the left photodiode PD group and the darklevel signal. Thus, by subtracting the dark level signal from thevoltage signal in the column signal processing circuit 5, the pixelsignal of the left photodiode PD group is obtained.

Next, the solid-state imaging device 1 turns on the reset transistor 53to reset the accumulated charges in the FD 52, and then reads a pixelsignal of the other of the left and right photodiode PD groups of thepixel set 51, for example, a pixel signal of the right photodiode PDgroup. In the example of the pixel set 51Gr illustrated in FIG. 4, afterthe selection transistor 55 is activated, the transfer transistorsTG_Gr1R, TG_Gr2R, TG_Gr3R, and TG_Gr4R are activated to transfer chargesaccumulated in the photodiodes PD_Gr1R, PD_Gr2R, PD_Gr3R, and PD_Gr4R tothe FD 52, so that a voltage signal corresponding to the accumulatedcharges in the FD 52 is output through the vertical signal line 9 to thecolumn signal processing circuit 5.

The voltage signal output to the column signal processing circuit 5 isthe sum of the pixel signal of the right photodiode PD group and thedark level signal. Thus, by subtracting the dark level signal from thevoltage signal in the column signal processing circuit 5, the pixelsignal of the right photodiode PD group is obtained.

In the first reading method, a pixel signal of the left photodiodes PDand a pixel signal of the right photodiodes PD are read separately, sothat a phase difference signal can be directly obtained. This allowsacquisition of a high-quality signal for distance measurement. On theother hand, a signal for a captured image can be obtained by digitallyadding signals of the left and right photodiodes PD.

Next, the second reading method will be described.

The second reading method is similar to the first reading method upuntil the acquisition of a dark level signal and the acquisition of apixel signal of one of the left and right photodiode PD groups in thepixel set 51 (a pixel signal of the left photodiode PD group).

After acquiring a pixel signal of one of the left and right photodiodePD groups, the solid-state imaging device 1 does not turn on the resettransistor 53 (keeps it off) unlike the first reading method, and readsa pixel signal of the other of the left and right photodiode PD groupsof the pixel set 51, for example, a pixel signal of the right photodiodePD group.

A voltage signal output to the column signal processing circuit 5 is thesum of the signals of the left and right photodiode PD groups and thedark level signal. The column signal processing circuit 5 first acquiresthe pixel signals of the left and right photodiode PD groups bysubtracting the dark level signal from the voltage signal, and thenacquires the pixel signal of the right photodiode PD group bysubtracting the pixel signal of the left photodiode PD group obtainedearlier from the pixel signals of the left and right photodiode PDgroups.

In the second reading method, the pixel signal of the left photodiodesPD and the pixel signal of the right photodiodes PD can be acquired asabove, and a phase difference signal can be obtained indirectly. On theother hand, signals for a captured image are added when they are analog,and thus have good signal quality, and also bring advantages in readingtime and power consumption as compared with the first reading method.

<5.3 Four-Pixel Addition Mode>

Next, a four-pixel addition mode will be described.

In a case where phase difference information is not required, thesolid-state imaging device 1 can execute the four-pixel addition mode inwhich pixel signals are added and output in each pixel set 51 that is asharing unit, that is, in units of four pixels in 2×2.

In the four-pixel addition mode, all the (eight) transfer transistors TGin the pixel set 51 that is a sharing unit are simultaneously turned on,and charges in all the photodiodes PD in the pixel set 51 are providedto the FD 52. The FD 52 adds the charges of all the photodiodes PD inthe pixel set 51. Then, a voltage signal corresponding to the addedcharges is output to the column signal processing circuit 5. By takingthe difference between the voltage signal and a dark level signal, apixel signal of each pixel set 51 can be acquired.

<5.4 First Phase Difference HDR Mode>

Next, a first phase difference HDR mode will be described.

The first phase difference HDR mode is an output mode that enablesdetection of a phase difference and generation of a high dynamic rangeimage (hereinafter, referred to as an HDR image).

In order to detect phase difference, at least some of the plurality ofpixels 2 constituting the pixel array 3 need to be pixels 2 that outputa pixel signal of the left photodiode PD and a pixel signal of the rightphotodiode PD individually.

Furthermore, in order to generate an HDR image, the plurality of pixels2 constituting the pixel array 3 needs to include pixels 2 different inexposure time.

Therefore, in the first phase difference HDR mode, the solid-stateimaging device 1 sets two types of exposure times for the plurality ofpixels 2 constituting the pixel array 3 as illustrated in FIG. 9.

FIG. 9 is a diagram illustrating the exposure times set for four (2×2)pixel sets 51 in a Bayer array that are a part of the pixel array 3 inthe first phase difference HDR mode.

In the first phase difference HDR mode, one of a first exposure time anda second exposure time is set for each pixel. The second exposure timeis an exposure time shorter than the first exposure time (first exposuretime>second exposure time). In FIG. 9, “L” is written in photodiodes PDfor which the first exposure time is set, and “S” is written inphotodiodes PD for which the second exposure time is set.

As illustrated in FIG. 9, the first exposure time and the secondexposure time are set with four pixels 2 constituting one pixel set 51paired in diagonal directions. For example, as in the example of FIG. 9,the first exposure time (L) is set for the two upper right and lowerleft pixels of the four pixels constituting the pixel set 51, and thesecond exposure time (S) is set for the two lower right and upper leftpixels. Note that the arrangement of the pixels 2 for which the firstexposure time (L) and the second exposure time (S) are set may bereversed.

FIG. 10 is a diagram illustrating a procedure of reading pixel signalsin the first phase difference HDR mode. Also in FIG. 10, a hatchedphotodiode PD represents a photodiode PD selected to output a pixelsignal.

In the first phase difference HDR mode, as illustrated in FIG. 10, thesolid-state imaging device 1 outputs pixel signals of all thephotodiodes PD for the two pixels for which the first exposure time (L)is set, and outputs pixel signals of the left photodiodes PD and pixelsignals of the right photodiodes PD separately for the two pixels forwhich the second exposure time (S) is set.

Specifically, the solid-state imaging device 1 simultaneously outputspixel signals of a plurality of photodiodes PD in the order of pixelsignals of all the photodiodes PD of the two upper right and lower leftpixels 2, pixel signals of the left photodiodes PD of the upper left andlower right pixels 2, and pixel signals of the upper left and lowerright right photodiodes PD.

Consequently, the two pixels 2 whose exposure time is set to the secondexposure time (S) output pixel signals of the left photodiode PD and theright photodiode PD separately, so that a phase difference can bedetected. Furthermore, since the pixels 2 for which the first exposuretime (L) is set and the pixels 2 for which the second exposure time (S)is set are included, an HDR image can be generated.

Note that the pixels 2 that detect a phase difference may be the pixels2 whose exposure time is set to the first exposure time (L). However, iflight intensity is high, the pixels 2 may be saturated. It is thuspreferable that the pixels 2 that detect a phase difference are thepixels 2 for which the second exposure time (S) is set. By using thepixels 2 for which the second exposure time (S) is set as phasedifference detection pixels, phase difference information can beacquired without causing saturation.

As described above, in the first phase difference HDR mode, for eachpixel set 51, two types of exposure times, the first exposure time (L)and the second exposure time (S), are set, and in some of the pixels 2of the pixel set 51, specifically, the pixels 2 for which the secondexposure time (S) is set, pixel signals of the left and rightphotodiodes PD are separately output to detect a phase difference, sothat signals for phase difference detection and signals of an HDR imagewith a high dynamic range can be simultaneously acquired.

<5.5 Second Phase Difference HDR Mode>

Next, a second phase difference HDR mode will be described.

Like the first phase difference HDR mode, the second phase differenceHDR mode is an output mode that enables phase difference detection andHDR image generation. The second phase difference HDR mode differs fromthe first phase difference HDR mode in that exposure times set for thepixels 2 in the pixel array 3 are not of the two types in the firstphase difference HDR mode but of three types.

FIG. 11 is a diagram illustrating exposure times set for four (2×2)pixel sets 51 in a Bayer array that are a part of the pixel array 3 inthe second phase difference HDR mode.

In the second phase difference HDR mode, one of first to third exposuretimes is set for each pixel. The second exposure time is an exposuretime shorter than the first exposure time, and the third exposure timeis an exposure time even shorter than the second exposure time (firstexposure time>second exposure time>third exposure time). In FIG. 11, “L”is written in photodiodes PD for which the first exposure time is set,“M” is written in photodiodes PD for which the second exposure time isset, and “S” is written in photodiodes PD for which the third exposuretime is set. Of the first exposure time (L), the second exposure time(M), and the third exposure time (S), the second exposure time (M) inthe middle is an exposure time suitable for proper exposure at the timeof automatic exposure.

As illustrated in FIG. 11, the second exposure time (M) is set for twopixels in a predetermined diagonal direction of four pixels 2constituting one pixel set 51, the first exposure time (L) is set forone of two pixels in the other diagonal direction, and the thirdexposure time (S) is set for the other. Note that the diagonal directionin which the second exposure time (M) is set may be a diagonally rightdirection instead of a diagonally left direction in FIG. 11.Furthermore, the arrangement of the pixels 2 for which the firstexposure time (L) and the third exposure time (S) are set may bereversed.

FIG. 12 is a diagram illustrating a procedure of reading pixel signalsin the second phase difference HDR mode. Also in FIG. 12, a hatchedphotodiode PD represents a photodiode PD selected to output a pixelsignal.

In the second phase difference HDR mode, as illustrated in FIG. 12, thesolid-state imaging device 1 outputs a pixel signal of the leftphotodiode PD and a pixel signal of the right photodiode PD separatelyfor the two pixels for which the second exposure time (M) is set, andoutputs a pixel signal of the photodiodes PD in each pixel as a unit forthe two pixels for which the first exposure time (L) and the thirdexposure time (S) are set.

Specifically, the solid-state imaging device 1 simultaneously outputspixel signals of a plurality of photodiodes PD in the order of pixelsignals of the two photodiodes PD of the upper right pixel 2, pixelsignals of the left photodiodes PD of the upper left and lower rightpixels 2, pixel signals of the right photodiodes PD of the upper leftand lower right pixels 2, and pixel signals of the two photodiodes PD ofthe lower left pixel 2.

Consequently, the two pixels 2 whose exposure time is set to the secondexposure time (M) output pixel signals of the left photodiode PD and theright photodiode PD separately, so that a phase difference can bedetected. Furthermore, since the pixels 2 for which the differentexposure times are set are included, an HDR image can be generated.

Note that the pixels 2 that detect a phase difference may be the pixels2 whose exposure time is set to the first exposure time (L) or the thirdexposure time (S). However, if light intensity is high, the pixels 2 maybe saturated, and if light intensity is low, the signal level may be toolow. It is thus preferable to use the pixels 2 for which the secondexposure time (M) for proper exposure is set. By using the pixels 2 forwhich the second exposure time (M) is set as phase difference detectionpixels, phase difference information can be acquired without causingsaturation.

As described above, in the second phase difference HDR mode, for eachpixel set 51, three types of exposure times, the first exposure time(L), the second exposure time (M), and the third exposure time (S), areset, and in some of the pixels 2 of each pixel set 51, specifically, thepixels 2 for which the second exposure time (M) is set, pixel signals ofthe left and right photodiodes PD are separately output to detect aphase difference, so that signals for phase difference detection andsignals of an HDR image with a high dynamic range can be simultaneouslyacquired.

Note that in order to enable operation in both the first phasedifference HDR mode and the second phase difference HDR mode, the eightsignal lines 61-1 to 61-8 or 62-1 to 62-8 as illustrated in FIG. 5 arerequired for the pixel sets 51 arranged in the horizontal direction.However, in a case where it is only required to enable operation in onlyone of the first phase difference HDR mode and the second phasedifference HDR mode, the number of signal lines for each pixel set 51arranged in the horizontal direction can be reduced.

For example, FIG. 13 illustrates a wiring example of signal lines in acase where operation in only the first phase difference HDR mode isenabled as an output mode that enables phase difference detection andHDR image generation.

In FIG. 13, by disposing four signal lines 81-1 to 81-4 for the pixelsets 51 arranged in the horizontal direction, operation in the firstphase difference HDR mode becomes possible.

Specifically, the single signal line 81-1 is disposed to control pixelsignals of the left photodiodes PD of the pixels 2 paired in thediagonal direction for which an exposure time of the second exposuretime (S) is set, and the single signal line 81-2 is disposed to controlpixel signals of the right photodiodes PD. Furthermore, the singlesignal line 81-3 is disposed to control pixel signals of the leftphotodiodes PD of the pixels 2 paired in the diagonal direction forwhich an exposure time of the first exposure time (L) is set, and thesingle signal line 81-4 is disposed to control pixel signals of theright photodiodes PD side.

FIG. 14 illustrates a wiring example of signal lines in a case whereoperation in only the second phase difference HDR mode is enabled as anoutput mode that enables phase difference detection and HDR imagegeneration.

In FIG. 14, by disposing six signal lines 82-1 to 82-6 for the pixelsets 51 arranged in the horizontal direction, operation in the secondphase difference HDR mode becomes possible.

Specifically, the single signal line 82-1 is disposed to control pixelsignals of the left photodiodes PD of the pixels 2 for which an exposuretime of the first exposure time (L) is set, and the single signal line82-2 is disposed to control pixel signals of the right photodiodes PD.Furthermore, the single signal line 82-3 is disposed to control pixelsignals of the left photodiodes PD of the pixels 2 paired in thediagonal direction for which an exposure time of the second exposuretime (M) is set, and the single signal line 82-4 is disposed to controlpixel signals of the right photodiodes PD. The single signal line 82-5is disposed to control pixel signals of the left photodiodes PD of thepixels 2 for which an exposure time of the third exposure time (S) isset, and the single signal line 82-6 is disposed to control pixelsignals of the right photodiodes PD.

As described above, the solid-state imaging device 1 can execute, as anoutput mode, the full-resolution mode in which pixel signals of thephotodiodes PD of each pixel 2 are output individually, the four-pixeladdition phase-difference detection mode in which pixel signals of theleft photodiodes PD or the right photodiodes PD are added and output inunits of four pixels, the four-pixel addition mode in which pixelsignals of all the photodiodes PD in the pixel set 51 are added andoutput, and the first phase difference HDR mode and the second phasedifference HDR mode that enable phase difference detection and HDR imagegeneration.

The full-resolution mode enables phase difference detection in all thepixels and high-resolution output by re-mosaicing, and the four-pixeladdition phase-difference detection mode enables phase differencedetection in the entire surface and high S/N and high dynamic rangesignal output by four-pixel addition. Furthermore, the four-pixeladdition mode enables high S/N and high dynamic range signal output byfour-pixel addition, and the first phase difference HDR mode and thesecond phase difference HDR mode enable both HDR image generation andphase difference detection in the entire surface. Note that to achieveHDR, two or more exposure times may be set for pixels with a singlesensitivity as described above, or a single exposure time may be set fora plurality of pixels with different sensitivities formed as a pixelset. An example of a plurality of pixels with different sensitivitiesincludes a pixel including photodiodes with a large light receiving areaas a pixel with a high sensitivity, and a pixel including photodiodeswith a small light receiving area as a pixel with a low sensitivity.

Note that, of course, the solid-state imaging device 1 may further beable to execute output modes other than those described above.

<6. Modification of color array of Color Filters>

FIG. 15 illustrates a modification of the color array of the colorfilters.

In the above-described example, as illustrated in FIG. 3 and others, theR, G, and B color filters 37 are arranged in the Bayer array in units ofthe pixel sets 51.

In contrast, in FIG. 15, the R, G, and B color filters 37 are arrangedin a Bayer array in units of the pixels 2.

Thus, the color filters 37 may be arranged in a Bayer array in units ofpixels.

The sharing unit of pixel circuits sharing the reset transistor 53, theamplification transistor 54, and the selection transistor 55 may be fourpixels in 2×2 (two vertical pixels×two horizontal pixels) as in FIG. 4,or may be four pixels in 4×1 (four vertical pixels×one horizontalpixel). The color array of the color filters 37 in the Bayer array inunits of pixels as illustrated in FIG. 15 allows pixel signals of pixelsof the same color to be added if four pixels in 4×1 are set as a sharingunit.

<7. Modification of Orientations of Photodiodes>

FIG. 16 illustrates a modification of the orientations of thephotodiodes PD.

In the above-described example, as illustrated in FIG. 3, the pairs ofphotodiodes PD in the pixels 2 are formed such that the orientations oftheir longitudinal shape are the same direction in each pixel set 51,and are also the same direction in all the pixel sets 51.

However, the orientations of the longitudinal shape of the pairs ofphotodiodes PD in the pixels may be different from pixel to pixel orfrom pixel set to pixel set.

A of FIG. 16 illustrates an example in which the pairs of photodiodes PDin the pixels 2 are formed such that the orientations of theirlongitudinal shape are the same direction in each pixel set 51, but aredifferent from pixel set 51 to pixel set 51.

In A of FIG. 16, the orientations of the longitudinal shape of the pairsof photodiodes PD in the pixel set 51Gr and the pixel set 51Gb includingthe G color filters 37 are the left-right direction (horizontaldirection), and the orientations of the longitudinal shape of the pairsof photodiodes PD in the pixel set 51R including the R color filters 37and the pixel set 51B including the B color filters 37 are theup-and-down direction (vertical direction). In other words, thephotodiodes PD are formed such that the orientations of the longitudinalshape of the pairs of photodiodes PD in the pixels are at right anglesbetween the pixel set 51Gr and the pixel set 51Gb, and the pixel set 51Rand the pixel set 51B. The orientations of the longitudinal shape of thephotodiodes PD in the pixel sets 51 including the color filters 37 ofthe same color are the same.

B of FIG. 16 illustrates an example in which in each pixel set 51including the color filters 37 of the same color, pairs of photodiodesPD in two pixels arranged in the horizontal direction are formed suchthat the orientations of their longitudinal shape are the samedirection, and pairs of photodiodes PD in two pixels arranged in thevertical direction are formed such that the orientations of theirlongitudinal shape are orthogonal directions.

In B of FIG. 16, in each pixel set 51, the photodiodes PD are formedsuch that the orientations of the longitudinal shape of the pairs ofphotodiodes PD in the two upper pixels are the left-right direction(horizontal direction), and the orientations of the longitudinal shapeof the pairs of photodiodes PD in the two lower pixels are theup-and-down direction (vertical direction).

C of FIG. 16 illustrates an example in which in each pixel set 51including the color filters 37 of the same color, pairs of photodiodesPD in two pixels PD arranged in the horizontal direction are formed suchthat the orientations of their longitudinal shape are orthogonaldirections, and pairs of photodiodes PD in two pixels PD arranged in thevertical direction are formed such that the orientations of theirlongitudinal shape are also orthogonal directions.

In C of FIG. 16, in each pixel set 51, the photodiodes PD are formedsuch that the orientations of the longitudinal shape of the pairs ofphotodiodes PD in the two upper pixels are the left-right direction(horizontal direction) and the up-and-down direction (verticaldirection), and the orientations of the longitudinal shape of the pairsof photodiodes PD in the two lower pixels are also the left-rightdirection (horizontal direction) and the up-and-down direction (verticaldirection).

As above, the two photodiodes PD of the longitudinal shape formed ineach pixel are arranged symmetrically in the vertical direction or thehorizontal direction, and for their orientations in the pixels in thepixel set 51, either the same direction or orthogonal directions can beused.

<8. Modification of On-Chip Lens Arrangement>

FIG. 17 illustrates a modification of the arrangement of the on-chiplenses 38.

In the above-described example, as illustrated in FIG. 3, the on-chiplenses 38 are formed for individual pixels.

However, as illustrated in FIG. 17, for some of the plurality of pixelsets 51 constituting the pixel array 3, one on-chip lens 91 may bedisposed for one pixel set 51.

A of FIG. 17 illustrates an example in which one on-chip lens 91 isdisposed for the pixel set 51Gb including the G color filters 37, andthe on-chip lenses 38 for individual pixels are disposed for the otherpixel sets 51Gr, 51R, and 51B.

B of FIG. 17 illustrates an example in which one on-chip lens 91 isdisposed for the pixel set 51R including the R color filters 37, and theon-chip lenses 38 for individual pixels are disposed for the other pixelsets 51Gr, 51Gb, and 51B.

C of FIG. 17 illustrates an example in which one on-chip lens 91 isdisposed for the pixel set 51B including the B color filters 37, and theon-chip lenses 38 for individual pixels are disposed for the other pixelsets 51Gr, 51R, and 51Gb.

In the pixel array 3 in which the pixel sets 51 are two-dimensionallyarranged, the on-chip lenses 91 in A to C of FIG. 17 may be disposed atregular intervals or randomly.

The pixel set 51 with the on-chip lens 91 cannot acquire pixel signalsfor generating an HDR image, but can detect a phase difference withpixel signals in each pixel, and thus is effective for phase differencedetection in low illumination.

<9. Second Cross-Sectional Configuration Example of Pixels>

FIG. 18 is a diagram illustrating a second cross-sectional configurationexample of the pixel array 3 of the solid-state imaging device 1 in FIG.1.

In FIG. 18, parts corresponding to those in the first cross-sectionalconfiguration example illustrated in FIG. 2 are denoted by the samereference numerals, and description of the parts will be omitted asappropriate.

The second cross-sectional configuration example of FIG. 18 differs fromthe first cross-sectional configuration example illustrated in FIG. 2 inthat an insulating layer 101 is formed in the semiconductor substrate12.

Specifically, in the first cross-sectional configuration exampleillustrated in FIG. 2, only the P-type semiconductor region 31 and theN-type semiconductor regions 32 are formed in the semiconductorsubstrate 12. In the second cross-sectional configuration example inFIG. 18, the insulating layer 101 is further formed at pixel boundariesbetween adjacent pixels and between the two photodiodes PD in eachpixel. The insulating layer 101 is formed, for example, by a deep trenchisolation (DTI) in which an oxide film (e.g., a TEOS film) is formed onthe inner peripheral surface of deep grooves (trenches) dug from theback side of the semiconductor substrate 12, and the inside thereof isfilled with polysilicon. Note that the insulating layer 101 is notlimited to the configuration using the oxide film and polysilicon, andmay be of a configuration using a metal such as hafnium or aconfiguration using an impurity layer. Furthermore, the insulating layer101 of different configurations may be applied in different pixels. Forexample, in an R pixel that transmits relatively long wavelengths, animpurity layer may be applied as the insulating layer 101, and in a Bpixel and a G pixel, an oxide film, polysilicon, or a metal may beapplied as the insulating layer 101. Furthermore, the insulating layer101 may be a shallow trench isolation (STI) shallower than DTI, or maybe a full trench isolation (FTI) that completely separates pixels fromeach other.

FIG. 19 is a plan view illustrating regions where the insulating layer101 is formed in a range of 16 pixels in 4×4.

As can be seen from the plan view of FIG. 19, the insulating layer 101is formed at the boundaries of the pixels 2 and between the twophotodiodes PD in each pixel, and the two photodiodes PD are separatedfrom each other by the insulating layer 101.

<10. Third Cross-Sectional Configuration Example of Pixels>

FIG. 20 is a diagram illustrating a third cross-sectional configurationexample of the pixel array 3 of the solid-state imaging device 1 in FIG.1.

In FIG. 20, parts corresponding to those in the second cross-sectionalconfiguration example illustrated in FIG. 18 are denoted by the samereference numerals, and description of the parts will be omitted asappropriate.

In the second cross-sectional configuration example of FIG. 18, theinsulating layer 101 is formed at the boundaries of the pixels 2 andbetween the two photodiodes PD in each pixel.

In the third cross-sectional configuration example of FIG. 20, at theboundaries of the pixels 2, the insulating layer 101 is formed as in thesecond cross-sectional configuration example, but between the twophotodiodes PD in each pixel, an impurity layer 102 of a conductivitytype opposite to that of the N-type semiconductor regions 32, that is,P-type is formed. The impurity concentration of the P-type impuritylayer 102 is higher than that of the semiconductor region 31. Theimpurity layer 102 can be formed, for example, by ion implantation fromthe back side of the semiconductor substrate 12.

FIG. 21 is a plan view illustrating regions where the insulating layer101 and the impurity layer 102 are formed in a range of 16 pixels in4×4.

As can be seen from the plan view of FIG. 21, the insulating layer 101is formed at the boundaries of the pixels 2, and the impurity layer 102separates the two photodiodes PD in each pixel from each other.

The potential barrier between the two photodiodes PD in each pixel maybe the same as the potential barrier at the pixel boundaries, or may bemade lower than the potential barrier at the pixel boundaries asillustrated in B of FIG. 22.

A of FIG. 22 is a cross-sectional structural diagram of one pixel in thethird cross-sectional configuration example, and B of FIG. 22 is apotential diagram corresponding to A of FIG. 22.

As illustrated in B of FIG. 22, by making the potential barrier betweenthe two photodiodes PD lower than that at the pixel boundaries, whencharges accumulated in one photodiode PD have reached a saturationlevel, they flow into the other photodiode PD before overflowing intothe FD 52. Thus, the linearity of a pixel signal of one pixel obtainedby combining the left and right photodiodes PD can be improved.

The height of the potential barrier between the photodiodes PD can bemade lower than the potential barrier at the pixel boundaries byadjusting the impurity concentration in the impurity layer 102.

Note that the impurity layer 102 may be formed so as to completelyisolate a region sandwiched between the two photodiodes PD asillustrated in FIG. 21, or may be formed so as to isolate only a part ofthe region sandwiched between the two photodiodes PD as illustrated inFIG. 23. In FIG. 23, the impurity layer 102 is formed only in a part inand around the pixel center of the region sandwiched between the twophotodiodes PD.

A cross-sectional view of parts where the impurity layer 102 is formedin FIG. 23 is the same as that in FIG. 20, and a cross-sectional view ofparts where the impurity layer 102 is not formed in FIG. 23 is the sameas that in FIG. 18.

<11. Configuration Example in which Light-Shielding Film is Added>

In the above-described example, the inter-pixel light-shielding film 36that prevent light from entering adjacent pixels are formed at pixelboundary portions, but no light-shielding film is formed on thephotodiodes PD.

However, for some of the pixels 2 in the pixel array 3, a configurationin which a light-shielding film is disposed on two photodiodes PD in apixel may be adopted.

FIG. 24 is a plan view illustrating a first configuration in which alight-shielding film is disposed on photodiodes PD.

In A and B of FIG. 24, in each pixel 2 of the pixel set 51Gr, the upperhalves or the lower halves of the two photodiodes PD in the pixel areshielded from the light by a light-shielding film 121.

A of FIG. 24 is an example in which the lower halves of the twophotodiodes PD in the pixel are shielded from the light by thelight-shielding film 121, and B of FIG. 24 is an example in which theupper halves of the two photodiodes PD in the pixel are shielded fromthe light by the light-shielding film 121.

The on-chip lenses 38 are formed for the individual pixels as in FIG. 3.

Using a pixel signal of the pixel set 51Gr in A of FIG. 24 in whichpieces of the light-shielding film 121 are symmetrically disposed (anadded pixel signal of the four pixels) and a pixel signal of the pixelset 51Gr in B of FIG. 24 (an added pixel signal of the four pixels),phase difference information is acquired.

FIG. 25 is a plan view illustrating a second configuration in which alight-shielding film is disposed on photodiodes PD.

In A and B of FIG. 25, in each pixel 2 of the pixel set 51Gr, one of thetwo photodiodes PD in the pixel is shielded from the light by thelight-shielding film 121.

A of FIG. 25 is an example in which the left photodiode PD of the twophotodiodes PD of each pixel 2 in the pixel set 51Gr is shielded fromthe light by the light-shielding film 121, and B of FIG. 25 is anexample in which the right photodiode PD of the two photodiodes PD ofeach pixel 2 in the pixel set 51Gr is shielded from the light by thelight-shielding film 121.

The on-chip lenses 38 are formed for the individual pixels as in FIG. 3.

Using a pixel signal of the pixel set 51Gr in A of FIG. 25 in whichpieces of the light-shielding film 121 are symmetrically disposed (anadded pixel signal of the four pixels) and a pixel signal of the pixelset 51Gr in B of FIG. 25 (an added pixel signal of the four pixels),phase difference information is acquired.

Both of the first and second configurations in FIGS. 24 and 25 are aconfiguration in which the light-shielding film 121 partly light-shieldsall the pixels 2 in the pixel set 51Gr.

FIG. 26 is a plan view illustrating a third configuration in which alight-shielding film is disposed on photodiodes PD.

In A and B of FIG. 26, of the four pixels constituting the pixel set51Gb, all the photodiodes PD of the two upper or lower pixels areshielded from the light by the light-shielding film 121.

A of FIG. 26 is an example in which all the photodiodes PD of the twolower pixels in the pixel set 51Gb are shielded from the light by thelight-shielding film 121, and B of FIG. 26 is an example in which allthe photodiodes PD of the two upper pixels in the pixel set 51Gb areshielded from the light by the light-shielding film 121.

In FIG. 26, one on-chip lens 91 is formed on the pixel set 51Gb at whichthe light-shielding film 121 is disposed, as in FIG. 17. On the pixelsets 51Gr, 51R, and 51B at which no light-shielding film 121 isdisposed, the on-chip lenses 38 for the individual pixels are formed.

Using a pixel signal of the pixel set 51Gb in A of FIG. 26 at whichpieces of the light-shielding film 121 are symmetrically disposed (anadded pixel signal of the four pixels) and a pixel signal of the pixelset 51Gb in B of FIG. 26 (an added pixel signal of the four pixels),phase difference information is acquired.

FIG. 27 is a plan view illustrating a fourth configuration in which alight-shielding film is disposed on photodiodes PD.

In A and B of FIG. 27, of the four pixels constituting the pixel set51Gb, all the photodiodes PD of the two left or right pixels areshielded from the light by the light-shielding film 121.

A of FIG. 27 is an example in which all the photodiodes PD of the twoleft pixels in the pixel set 51Gb are shielded from the light by thelight-shielding film 121, and B of FIG. 27 is an example in which allthe photodiodes PD of the two right pixels in the pixel set 51Gb areshielded from the light by the light-shielding film 121.

In FIG. 27, one on-chip lens 91 is formed on the pixel set 51Gb at whichthe light-shielding film 121 is disposed, as in FIG. 17. On the pixelsets 51Gr, 51R, and 51B at which no light-shielding film 121 isdisposed, the on-chip lenses 38 for the individual pixels are formed.

Using a pixel signal of the pixel set 51Gb in A of FIG. 27 at whichpieces of the light-shielding film 121 are symmetrically disposed (anadded pixel signal of the four pixels) and a pixel signal of the pixelset 51Gb in B of FIG. 27 (an added pixel signal of the four pixels),phase difference information is acquired.

Both of the third and fourth configurations in FIGS. 26 and 27 are aconfiguration in which the light-shielding film 121 entirely shieldssome of the pixels 2 in the pixel set 51Gr from the light.

In a case where the light intensity of incident light is high and phasedifference information cannot be acquired in the pixel sets 51 at whichno light-shielding film 121 is disposed, the first to fourthconfigurations of FIG. 24 to FIG. 27 in which the light-shielding film121 is disposed allows the pixel sets 51 at which the light-shieldingfilm 121 is disposed to acquire phase difference information. Thus, thefirst to fourth configurations in which the light-shielding film 121 isdisposed are effective in acquiring phase difference information in acase where the light intensity of incident light is high.

The first to fourth configurations of FIGS. 24 to 27 in which thelight-shielding film is disposed are an example in which thelight-shielding film 121 is disposed at the pixel set 51Gb or the pixelset 51Gr. A similar light-shielding film 121 may be formed for the otherpixel set 51R or 51B, or the light-shielding film 121 may be formed atall of the pixel sets 51Gb, 51R, and 51B.

<12. Other Modifications>

FIG. 28 illustrates another modification of the solid-state imagingdevice 1.

In the example described above, the constituent units of the pixel set51 is four pixels in 2×2 (two vertical pixels×two horizontal pixels).However, the pixel set 51 is not limited to four pixels in 2×2, and isonly required to include a plurality of pixels 2.

FIG. 28 illustrates an example in which the constituent units of thepixel set 51 is 16 pixels in 4×4 (four vertical pixels×four horizontalpixels). The example of FIG. 28 illustrates an example in which anon-chip lens 38 is formed for each pixel, which is not limiting. Oneon-chip lens may be disposed for four pixels in 2×2, or one on-chip lensmay be disposed for 16 pixels in 4×4.

In addition, for example, nine pixels in 3×3 (three verticalpixels×three horizontal pixels) may be set as constituent units of thepixel set 51.

FIG. 29 illustrates still another modification of the solid-stateimaging device 1.

In the example described above, a color filter 37 that allows light ofwavelengths of R, G, or B to pass through is formed at each pixel 2 ofthe solid-state imaging device 1.

However, as illustrated in FIG. 29, a configuration in which the colorfilters 37 are eliminated may be adopted. In this case, the pixels 2 ofthe solid-state imaging device 1 can receive light of all wavelengths ofR, G, and B to generate and output pixel signals.

Alternatively, instead of the color filters 37, the solid-state imagingdevice 1 may be provided with infrared filters that transmit infraredlight to receive only infrared light to generate and output pixelsignals.

<13. Pixel transistor Arrangement Example>

An example of arrangement of pixel transistors will be described withreference to FIG. 30.

In the pixel array 3, for example, the arrangement of the photodiodes PDand the pixel transistors illustrated in FIG. 30 is repeated in thehorizontal direction and the vertical direction.

FIG. 30 is a plan view illustrating an example of arrangement of thepixel transistors in a pixel region of a total of 16 pixels in which thepixel sets 51 whose constituent units are four pixels in 2×2 (twovertical pixels×two horizontal pixels) are arranged 2×2. In FIG. 30, aportion indicated by a black circle represents a power supply, a GND, ora contact portion of a signal line. Note that in FIG. 30, some referencenumerals are omitted to prevent the figure from being complicated.

In FIG. 30, the photodiodes PD, the color filters 37 (not illustrated inFIG. 30), and the on-chip lenses 38 are formed as in the exampleillustrated in FIG. 3. Specifically, two photodiodes PD are disposed forone pixel horizontally symmetrically in a longitudinal shape. Theon-chip lenses 38 are formed for the individual pixels. The colorfilters 37 are arranged in a Bayer array in units of the pixel sets 51.The upper left pixel set 51 is the pixel set 51Gr including the G colorfilters 37, the upper right pixel set 51 is the pixel set 51R includingthe R color filters 37, the lower left pixel set 51 is the pixel set 51Bincluding the B color filters 37, and the lower right pixel set 51 isthe pixel set 51Gb including the G color filters 37.

As described with reference to FIG. 4, one pixel set 51 including fourpixels is provided with eight photodiodes PD and eight transfertransistors TG, and the FD 52, the reset transistor 53, theamplification transistor 54, and the selection transistor 55 shared bythem.

As illustrated in FIG. 30, the eight photodiodes PD included in onepixel set 51 are arrayed in 2×4 (vertically two×horizontally four), andthe reset transistor 53, the amplification transistor 54, and theselection transistor 55, which are shared by the eight photodiodes PD,are disposed vertically (longitudinally) adjacent to the eightphotodiodes PD in 2×4. If the reset transistor 53, the amplificationtransistor 54, and the selection transistor 55, which are shared by theeight photodiodes PD, are collectively referred to as shared pixeltransistors, the shared pixel transistors are disposed between the eightphotodiodes PD and the eight photodiodes PD in 2×4 in the two verticallyadjacent pixel sets 51.

With four photodiodes PD in 2×2 as a group, the transfer transistors TGprovided one-to-one to the photodiodes PD are disposed near the centerof the group. Four transfer transistors TG are collectively disposednear the center of four photodiodes PD in 2×2 in a right group in thepixel set 51, and four transfer transistors TG are collectively disposednear the center of four photodiodes PD in 2×2 in a left group in thepixel set 51.

The FD 52 includes at least metal wiring 52A as a part thereof. Asillustrated in FIG. 30, the metal wiring 52A is routed to electricallyconnect a middle portion of the four photodiodes PD in 2×2 in the rightgroup in the pixel set 51, a middle portion of the four photodiodes PDin 2×2 in the left group in the pixel set 51, the gate electrode of theamplification transistor 54, and the source electrode of the resettransistor 53. Charges accumulated in each photodiode PD in the pixelset 51 are transferred to the metal wiring 52A constituting a part ofthe FD 52 by the corresponding transfer transistor TG, transmittedthrough the metal wiring 52A, and provided to the gate electrode of theamplification transistor 54. Furthermore, when the reset transistor 53is turned on, charges in the FD 52 are discharged from the sourceelectrode to the drain electrode of the reset transistor 53.

Thus, for the shared pixel transistors (the reset transistor 53, theamplification transistor 54, and the selection transistor 55), a layoutcan be adopted in which they are disposed between the eight photodiodesPD of one pixel set 51 and the eight photodiodes PD of another pixel set51 adjacent in the column direction. Note that although not illustrated,a layout in which the shared pixel transistors are disposed between theeight photodiodes PD and the eight photodiodes PD of the pixel sets 51adjacent to each other in the row direction may be used.

<14. Example of Application to Electronic Apparatus>

The present technology is not limited to application to a solid-stateimaging device. Specifically, the present technology is applicable toall electronic apparatuses using a solid-state imaging device for animage capturing unit (photoelectric conversion part), such as imagingapparatuses including digital still cameras and video cameras, portableterminal devices having an imaging function, and copying machines usinga solid-state imaging device for an image reading unit. The solid-stateimaging device may be formed as one chip, or may be in a modular formhaving an imaging function in which an imaging unit and a signalprocessing unit or an optical system are packaged together.

FIG. 31 is a block diagram illustrating a configuration example of animaging apparatus as an electronic apparatus to which the presenttechnology is applied.

An imaging apparatus 200 in FIG. 31 includes an optical unit 201including a lens group or the like, a solid-state imaging device(imaging device) 202 in which the configuration of the solid-stateimaging device 1 in FIG. 1 is used, and a digital signal processor (DSP)circuit 203 that is a camera signal processing circuit. Furthermore, theimaging apparatus 200 also includes a frame memory 204, a display unit205, a recording unit 206, an operation unit 207, and a power supply208. The DSP circuit 203, the frame memory 204, the display unit 205,the recording unit 206, the operation unit 207, and the power supply 208are mutually connected via a bus line 209.

The optical unit 201 captures incident light (image light) from asubject, forming an image on an imaging surface of the solid-stateimaging device 202. The solid-state imaging device 202 converts theamount of incident light formed as the image on the imaging surface bythe optical unit 201 into an electric signal pixel by pixel and outputsthe electric signal as a pixel signal. As the solid-state imaging device202, the solid-state imaging device 1 in FIG. 1, that is, a solid-stateimaging device capable of simultaneously acquiring a signal forgenerating a high dynamic range image and a signal for detecting a phasedifference can be used.

The display unit 205 includes, for example, a thin display such as aliquid crystal display (LCD) or an organic electroluminescence (EL)display, and displays a moving image or a still image captured by thesolid-state imaging device 202. The recording unit 206 records a movingimage or a still image captured by the solid-state imaging device 202 ona recording medium such as a hard disk or a semiconductor memory.

The operation unit 207 issues operation commands on various functions ofthe imaging apparatus 200 under user operation. The power supply 208appropriately supplies various power supplies to be operation powersupplies for the DSP circuit 203, the frame memory 204, the display unit205, the recording unit 206, and the operation unit 207, to them to besupplied with.

As described above, by using the solid-state imaging device 1 to whichthe above-described embodiment is applied as the solid-state imagingdevice 202, it is possible to simultaneously acquire a signal forgenerating a high dynamic range image and a signal for detecting a phasedifference. Therefore, the imaging apparatus 200 such as a video cameraor a digital still camera, or further a camera module for a mobiledevice such as a portable phone can also improve the quality of capturedimages.

<Example of Use of Image Sensor>

FIG. 32 is a diagram illustrating an example of use of an image sensorusing the above-described solid-state imaging device 1.

The image sensor using the above-described solid-state imaging device 1can be used in various cases where light such as visible light, infraredlight, ultraviolet light, and X-ray are sensed, for example, as below.

Devices for capturing images for viewing, such as digital cameras andportable devices with a camera function

Devices for transportation use, such as vehicle-mounted sensors forimaging the front, back, surroundings, interior, etc. of a vehicle,surveillance cameras for monitoring running vehicles and roads, anddistance measurement sensors for measuring distance between vehicles orthe like, for safe driving such as automatic stopping, recognition ofdrivers' conditions, and the like

Devices used in household appliances such as TVs, refrigerators, and airconditioners, for imaging user gestures and performing apparatusoperations in accordance with the gestures

Devices for medical treatment and healthcare use, such as endoscopes anddevices that perform blood vessel imaging through reception of infraredlight

Devices for security use, such as surveillance cameras for crimeprevention applications and cameras for person authenticationapplications

Devices for beautification use, such as skin measuring instruments forimaging skin and microscopes for imaging scalp

Devices for sports use, such as action cameras and wearable cameras forsports applications and the like

Devices for agriculture use, such as cameras for monitoring theconditions of fields and crops

<15. Example of Application to Endoscopic Surgery System>

The technology according to the present disclosure (the presenttechnology) can be applied to various products. For example, thetechnology according to the present disclosure may be applied to anendoscopic surgery system.

FIG. 33 is a diagram illustrating an example of a schematicconfiguration of an endoscopic surgery system to which the technologyaccording to the present disclosure (the present technology) can beapplied.

FIG. 33 illustrates a state in which an operator (doctor) 11131 isperforming an operation on a patient 11132 on a patient bed 11133, usingan endoscopic surgery system 11000. As illustrated in the figure, theendoscopic surgery system 11000 includes an endoscope 11100, othersurgical instruments 11110 including a pneumoperitoneum tube 11111 andan energy treatment instrument 11112, a support arm device 11120 thatsupports the endoscope 11100, and a cart 11200 on which various devicesfor endoscopic surgery are mounted.

The endoscope 11100 includes a lens tube 11101 with a region of apredetermined length from the distal end inserted into the body cavityof the patient 11132, and a camera head 11102 connected to the proximalend of the lens tube 11101. In the illustrated example, the endoscope11100 formed as a so-called rigid scope having a rigid lens tube 11101is illustrated, but the endoscope 11100 may be formed as a so-calledflexible scope having a flexible lens tube.

An opening in which an objective lens is fitted is provided at thedistal end of the lens tube 11101. A light source device 11203 isconnected to the endoscope 11100. Light generated by the light sourcedevice 11203 is guided to the distal end of the lens tube 11101 througha light guide extended inside the lens tube 11101, and is emittedthrough the objective lens toward an object to be observed in the bodycavity of the patient 11132. Note that the endoscope 11100 may be aforward-viewing endoscope, an oblique-viewing endoscope, or aside-viewing endoscope.

An optical system and an imaging device are provided inside the camerahead 11102. Light reflected from the object being observed (observationlight) is concentrated onto the imaging device by the optical system.The observation light is photoelectrically converted by the imagingdevice, and an electric signal corresponding to the observation light,that is, an image signal corresponding to an observation image isgenerated. The image signal is transmitted to a camera control unit(CCU) 11201 as RAW data.

The CCU 11201 includes a central processing unit (CPU), a graphicsprocessing unit (GPU), or the like, and performs centralized control onthe operations of the endoscope 11100 and a display device 11202.Moreover, the CCU 11201 receives an image signal from the camera head11102, and performs various types of image processing such asdevelopment processing (demosaicing) on the image signal for displayingan image based on the image signal.

The display device 11202 displays an image based on an image signalsubjected to image processing by the CCU 11201 under the control of theCCU 11201.

The light source device 11203 includes a light source such as a lightemitting diode (LED), and supplies irradiation light when a surgicalsite or the like is imaged to the endoscope 11100.

An input device 11204 is an input interface for the endoscopic surgerysystem 11000. The user can input various types of information and inputinstructions to the endoscopic surgery system 11000 via the input device11204. For example, the user inputs an instruction to change conditionsof imaging by the endoscope 11100 (the type of irradiation light,magnification, focal length, etc.) and the like.

A treatment instrument control device 11205 controls the drive of theenergy treatment instrument 11112 for tissue ablation, incision, bloodvessel sealing, or the like. A pneumoperitoneum device 11206 feeds gasinto the body cavity of the patient 11132 through the pneumoperitoneumtube 11111 to inflate the body cavity for the purpose of providing afield of view by the endoscope 11100 and providing the operator'sworkspace. A recorder 11207 is a device that can record various types ofinformation associated with surgery. A printer 11208 is a device thatcan print various types of information associated with surgery invarious forms including text, an image, and a graph.

Note that the light source device 11203 that supplies irradiation lightwhen a surgical site is imaged to the endoscope 11100 may include awhite light source including LEDs, laser light sources, or a combinationof them, for example. In a case where a white light source includes acombination of RGB laser light sources, the output intensity and outputtiming of each color (each wavelength) can be controlled with highaccuracy. Thus, the light source device 11203 can adjust the whitebalance of captured images. Furthermore, in this case, by irradiating anobject to be observed with laser light from each of the RGB laser lightsources in a time-division manner, and controlling the drive of theimaging device of the camera head 11102 in synchronization with theirradiation timing, images corresponding one-to-one to RGB can also beimaged in a time-division manner. According to this method, color imagescan be obtained without providing color filters at the imaging device.

Furthermore, the drive of the light source device 11203 may becontrolled so as to change the intensity of output light everypredetermined time. By controlling the drive of the imaging device ofthe camera head 11102 in synchronization with the timing of change ofthe intensity of light and acquiring images in a time-division manner,and combining the images, a high dynamic range image without so-calledunderexposure and overexposure can be generated.

Furthermore, the light source device 11203 may be configured to be ableto supply light in a predetermined wavelength band suitable for speciallight observation. In special light observation, for example, so-callednarrow band imaging is performed in which predetermined tissue such as ablood vessel in a superficial portion of a mucous membrane is imagedwith high contrast by irradiating it with light in a narrower band thanirradiation light at the time of normal observation (that is, whitelight), utilizing the wavelength dependence of light absorption in bodytissue. Alternatively, in special light observation, fluorescenceobservation may be performed in which an image is obtained byfluorescence generated by irradiation with excitation light.Fluorescence observation allows observation of fluorescence from bodytissue by irradiating the body tissue with excitation light(autofluorescence observation), acquisition of a fluorescence image bylocally injecting a reagent such as indocyanine green (ICG) into bodytissue and irradiating the body tissue with excitation lightcorresponding to the fluorescence wavelength of the reagent, and thelike. The light source device 11203 can be configured to be able tosupply narrowband light and/or excitation light suitable for suchspecial light observation.

FIG. 34 is a block diagram illustrating an example of a functionalconfiguration of the camera head 11102 and the CCU 11201 illustrated inFIG. 33.

The camera head 11102 includes a lens unit 11401, an imaging unit 11402,a drive unit 11403, a communication unit 11404, and a camera headcontrol unit 11405. The CCU 11201 includes a communication unit 11411,an image processing unit 11412, and a control unit 11413. The camerahead 11102 and the CCU 11201 are communicably connected to each other bya transmission cable 11400.

The lens unit 11401 is an optical system provided at a portion connectedto the lens tube 11101. Observation light taken in from the distal endof the lens tube 11101 is guided to the camera head 11102 and enters thelens unit 11401. The lens unit 11401 includes a combination of aplurality of lenses including a zoom lens and a focus lens.

The imaging unit 11402 includes an imaging device. The imaging unit11402 may include a single imaging device (be of a so-called singleplate type), or may include a plurality of imaging devices (be of aso-called multi-plate type). In a case where the imaging unit 11402 isof the multi-plate type, for example, image signals correspondingone-to-one to RGB may be generated by imaging devices, and they may becombined to obtain a color image. Alternatively, the imaging unit 11402may include a pair of imaging devices for acquiring right-eye andleft-eye image signals corresponding to a 3D (dimensional) display,individually. By performing 3D display, the operator 11131 can moreaccurately grasp the depth of living tissue at a surgical site. Notethat in a case where the imaging unit 11402 is of the multi-plate type,a plurality of lens units 11401 may be provided for the correspondingimaging devices.

Furthermore, the imaging unit 11402 may not necessarily be provided inthe camera head 11102. For example, the imaging unit 11402 may beprovided inside the lens tube 11101 directly behind the objective lens.

The drive unit 11403 includes an actuator, and moves the zoom lens andthe focus lens of the lens unit 11401 by a predetermined distance alongthe optical axis under the control of the camera head control unit11405. With this, the magnification and focus of an image captured bythe imaging unit 11402 can be adjusted as appropriate.

The communication unit 11404 includes a communication device fortransmitting and receiving various types of information to and from theCCU 11201. The communication unit 11404 transmits an image signalobtained from the imaging unit 11402 as RAW data to the CCU 11201 viathe transmission cable 11400.

Furthermore, the communication unit 11404 receives a control signal forcontrolling the drive of the camera head 11102 from the CCU 11201, andprovides the control signal to the camera head control unit 11405. Thecontrol signal includes, for example, information regarding imagingconditions such as information specifying the frame rate of capturedimages, information specifying the exposure value at the time ofimaging, and/or information specifying the magnification and focus ofcaptured images.

Note that the imaging conditions such as the frame rate, the exposurevalue, the magnification, and the focus described above may beappropriately specified by the user, or may be automatically set by thecontrol unit 11413 of the CCU 11201 on the basis of an acquired imagesignal. In the latter case, so-called an auto exposure (AE) function, anauto focus (AF) function, and an auto white balance (AWB) function aremounted on the endoscope 11100.

The camera head control unit 11405 controls the drive of the camera head11102 on the basis of a control signal from the CCU 11201 received viathe communication unit 11404.

The communication unit 11411 includes a communication device fortransmitting and receiving various types of information to and from thecamera head 11102. The communication unit 11411 receives an image signaltransmitted from the camera head 11102 via the transmission cable 11400.

Furthermore, the communication unit 11411 transmits a control signal forcontrolling the drive of the camera head 11102 to the camera head 11102.The image signal and the control signal can be transmitted by electricalcommunication, optical communication, or the like.

The image processing unit 11412 performs various types of imageprocessing on an image signal that is RAW data transmitted from thecamera head 11102.

The control unit 11413 performs various types of control for imaging ofa surgical site or the like by the endoscope 11100 and display of acaptured image obtained by imaging of a surgical site or the like. Forexample, the control unit 11413 generates a control signal forcontrolling the drive of the camera head 11102.

Furthermore, the control unit 11413 causes the display device 11202 todisplay a captured image showing a surgical site or the like, on thebasis of an image signal subjected to image processing by the imageprocessing unit 11412. At this time, the control unit 11413 mayrecognize various objects in the captured image using various imagerecognition techniques. For example, by detecting the shape of the edge,the color, or the like of an object included in a captured image, thecontrol unit 11413 can recognize a surgical instrument such as forceps,a specific living body part, bleeding, mist when the energy treatmentinstrument 11112 is used, and so on. When causing the display device11202 to display a captured image, the control unit 11413 maysuperimpose various types of surgery support information on an image ofthe surgical site for display, using the recognition results. By thesurgery support information being superimposed and displayed, andpresented to the operator 11131, the load of the operator 11131 can bereduced, and the operator 11131 can reliably proceed with the surgery.

The transmission cable 11400 that connects the camera head 11102 and theCCU 11201 is an electric signal cable for electric signal communication,an optical fiber for optical communication, or a composite cable forthem.

Here, in the illustrated example, communication is performed by wireusing the transmission cable 11400, but communication between the camerahead 11102 and the CCU 11201 may be performed by radio.

An example of the endoscopic surgery system to which the technologyaccording to the present disclosure can be applied has so far beendescribed. The technology according to the present disclosure can beapplied to the imaging unit 11402 in the configuration described above.Specifically, the solid-state imaging device 1 according to theabove-described embodiment can be applied as the imaging unit 11402. Byapplying the technology according to the present disclosure to theimaging unit 11402, it is possible to simultaneously acquire a signalfor generating a high dynamic range image and a signal for detecting aphase difference. Consequently, a high-quality captured image anddistance information can be acquired, and the degree of safety of thedriver and the vehicle can be increased.

Note that although the endoscopic surgery system has been described hereas an example, the technology according to the present disclosure may beapplied, for example, to a microsurgery system and the like.

<16. Example of Application to Mobile Object>

The technology according to the present disclosure (the presenttechnology) can be applied to various products. For example, thetechnology according to the present disclosure may be implemented as adevice mounted on any type of mobile object such as an automobile, anelectric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle,personal mobility, an airplane, a drone, a ship, and a robot.

FIG. 35 is a block diagram illustrating a schematic configurationexample of a vehicle control system that is an example of a mobileobject control system to which the technology according to the presentdisclosure can be applied.

A vehicle control system 12000 includes a plurality of electroniccontrol units connected via a communication network 12001. In theexample illustrated in FIG. 35, the vehicle control system 12000includes a drive system control unit 12010, a body system control unit12020, a vehicle exterior information detection unit 12030, a vehicleinterior information detection unit 12040, and an integrated controlunit 12050. Furthermore, as a functional configuration of the integratedcontrol unit 12050, a microcomputer 12051, a sound/image output unit12052, and an in-vehicle network interface (I/F) 12053 are illustrated.

The drive system control unit 12010 controls the operation ofapparatuses related to the drive system of the vehicle, according tovarious programs. For example, the drive system control unit 12010functions as a control device for a driving force generation apparatusfor generating a driving force of the vehicle such as an internalcombustion engine or a drive motor, a driving force transmissionmechanism for transmitting the driving force to wheels, a steeringmechanism for adjusting the steering angle of the vehicle, a brakingdevice for generating a vehicle braking force, and others.

The body system control unit 12020 controls the operation of variousapparatuses mounted on the vehicle body, according to various programs.For example, the body system control unit 12020 functions as a controldevice for a keyless entry system, a smart key system, power windowdevices, or various lamps including headlamps, back lamps, brake lamps,indicators, and fog lamps. In this case, the body system control unit12020 can receive the input of radio waves transmitted from a portabledevice that substitutes for a key or signals from various switches. Thebody system control unit 12020 receives the input of these radio wavesor signals, and controls door lock devices, the power window devices,the lamps, and others of the vehicle.

The vehicle exterior information detection unit 12030 detectsinformation regarding the exterior of the vehicle equipped with thevehicle control system 12000. For example, an imaging unit 12031 isconnected to the vehicle exterior information detection unit 12030. Thevehicle exterior information detection unit 12030 causes the imagingunit 12031 to capture an image outside the vehicle and receives thecaptured image. The vehicle exterior information detection unit 12030may perform object detection processing or distance detection processingon a person, a vehicle, an obstacle, a sign, characters on a roadsurface, or the like, on the basis of the received image.

The imaging unit 12031 is an optical sensor that receives light andoutputs an electric signal corresponding to the amount of the receivedlight. The imaging unit 12031 may output an electric signal as an image,or may output it as distance measurement information. Furthermore, lightreceived by the imaging unit 12031 may be visible light, or may beinvisible light such as infrared rays.

The vehicle interior information detection unit 12040 detectsinformation of the vehicle interior. For example, a driver conditiondetection unit 12041 that detects a driver's conditions is connected tothe vehicle interior information detection unit 12040. The drivercondition detection unit 12041 includes, for example, a camera thatimages the driver. The vehicle interior information detection unit 12040may calculate the degree of fatigue or the degree of concentration ofthe driver, or may determine whether the driver is dozing, on the basisof detected information input from the driver condition detection unit12041.

The microcomputer 12051 can calculate a control target value for thedriving force generation apparatus, the steering mechanism, or thebraking device on the basis of vehicle interior or exterior informationacquired by the vehicle exterior information detection unit 12030 or thevehicle interior information detection unit 12040, and output a controlcommand to the drive system control unit 12010. For example, themicrocomputer 12051 can perform cooperative control for the purpose ofimplementing the functions of an advanced driver assistance system(ADAS) including vehicle collision avoidance or impact mitigation,following driving based on inter-vehicle distance, vehiclespeed-maintaining driving, vehicle collision warning, vehicle lanedeparture warning, and so on.

Furthermore, the microcomputer 12051 can perform cooperative control forthe purpose of automatic driving for autonomous traveling without adriver's operation, by controlling the driving force generationapparatus, the steering mechanism, the braking device, or others, on thebasis of information around the vehicle acquired by the vehicle exteriorinformation detection unit 12030 or the vehicle interior informationdetection unit 12040.

Moreover, the microcomputer 12051 can output a control command to thebody system control unit 12020 on the basis of vehicle exteriorinformation acquired by the vehicle exterior information detection unit12030. For example, the microcomputer 12051 can perform cooperativecontrol for the purpose of preventing glare by controlling the headlampsaccording to the position of a preceding vehicle or an oncoming vehicledetected by the vehicle exterior information detection unit 12030,switching high beam to low beam, or the like.

The sound/image output unit 12052 transmits an output signal of at leastone of a sound or an image to an output device that can visually orauditorily notify a vehicle occupant or the outside of the vehicle ofinformation. In the example of FIG. 35, as the output device, an audiospeaker 12061, a display unit 12062, and an instrument panel 12063 areillustrated. The display unit 12062 may include at least one of anon-board display or a head-up display, for example.

FIG. 36 is a diagram illustrating an example of the installationposition of the imaging unit 12031.

In FIG. 36, a vehicle 12100 includes imaging units 12101, 12102, 12103,12104, and 12105 as the imaging unit 12031.

The imaging units 12101, 12102, 12103, 12104, and 12105 are provided,for example, at positions such as the front nose, the side mirrors, therear bumper or the back door, and an upper portion of the windshield inthe vehicle compartment of the vehicle 12100. The imaging unit 12101provided at the front nose and the imaging unit 12105 provided at theupper portion of the windshield in the vehicle compartment mainlyacquire images of the front of the vehicle 12100. The imaging units12102 and 12103 provided at the side mirrors mainly acquire images ofthe sides of the vehicle 12100. The imaging unit 12104 provided at therear bumper or the back door mainly acquires images of the rear of thevehicle 12100. Front images acquired by the imaging units 12101 and12105 are mainly used for detection of a preceding vehicle, or apedestrian, an obstacle, a traffic light, or a traffic sign, or a lane,or the like.

Note that FIG. 36 illustrates an example of imaging ranges of theimaging units 12101 to 12104. An imaging range 12111 indicates theimaging range of the imaging unit 12101 provided at the front nose,imaging ranges 12112 and 12113 indicate the imaging ranges of theimaging units 12102 and 12103 provided at the side mirrors,respectively, and an imaging range 12114 indicates the imaging range ofthe imaging unit 12104 provided at the rear bumper or the back door. Forexample, by superimposing image data captured by the imaging units 12101to 12104 on each other, an overhead image of the vehicle 12100 viewedfrom above is obtained.

At least one of the imaging units 12101 to 12104 may have a function ofacquiring distance information. For example, at least one of the imagingunits 12101 to 12104 may be a stereo camera including a plurality ofimaging devices, or may be an imaging device including pixels for phasedifference detection.

For example, the microcomputer 12051 can determine distances tothree-dimensional objects in the imaging ranges 12111 to 12114, andtemporal changes in the distances (relative speeds to the vehicle12100), on the basis of distance information obtained from the imagingunits 12101 to 12104, thereby extracting, as a preceding vehicle,especially the nearest three-dimensional object located on the travelingpath of the vehicle 12100 which is a three-dimensional object travelingat a predetermined speed (e.g., 0 km/h or higher) in substantially thesame direction as the vehicle 12100. Furthermore, the microcomputer12051 can perform automatic brake control (including following stopcontrol), automatic acceleration control (including following startcontrol), and the like, setting an inter-vehicle distance to be providedin advance in front of a preceding vehicle. Thus, cooperative controlfor the purpose of autonomous driving for autonomous traveling without adriver's operation or the like can be performed.

For example, the microcomputer 12051 can extract three-dimensionalobject data regarding three-dimensional objects, classifying them into atwo-wheel vehicle, an ordinary vehicle, a large vehicle, a pedestrian,and another three-dimensional object such as a power pole, on the basisof distance information obtained from the imaging units 12101 to 12104,for use in automatic avoidance of obstacles. For example, for obstaclesaround the vehicle 12100, the microcomputer 12051 distinguishes betweenobstacles that can be visually identified by the driver of the vehicle12100 and obstacles that are difficult to visually identify. Then, themicrocomputer 12051 determines a collision risk indicating the degree ofdanger of collision with each obstacle. In a situation where thecollision risk is equal to or higher than a set value and there is apossibility of collision, the microcomputer 12051 can perform drivingassistance for collision avoidance by outputting a warning to the drivervia the audio speaker 12061 or the display unit 12062, or performingforced deceleration or avoidance steering via the drive system controlunit 12010.

At least one of the imaging units 12101 to 12104 may be an infraredcamera that detects infrared rays. For example, the microcomputer 12051can recognize a pedestrian by determining whether or not a pedestrian ispresent in captured images of the imaging units 12101 to 12104. Therecognition of a pedestrian is performed, for example, by a procedure ofextracting feature points in captured images of the imaging units 12101to 12104 as infrared cameras, and a procedure of performing patternmatching on a series of feature points indicating the outline of anobject to determine whether or not the object is a pedestrian. When themicrocomputer 12051 determines that a pedestrian is present in capturedimages of the imaging units 12101 to 12104 and recognizes thepedestrian, the sound/image output unit 12052 controls the display unit12062 to superimpose and display a rectangular outline for enhancementon the recognized pedestrian. Alternatively, the sound/image output unit12052 may control the display unit 12062 so as to display an icon or thelike indicating the pedestrian at a desired position.

An example of the vehicle control system to which the technologyaccording to the present disclosure can be applied has so far beendescribed. The technology according to the present disclosure can beapplied to the imaging unit 12031 in the configuration described above.Specifically, the solid-state imaging device 1 according to theabove-described embodiment can be applied as the imaging unit 12031. Byapplying the technology according to the present disclosure to theimaging unit 12031, a signal for generating a high dynamic range imageand a signal for detecting a phase difference can be acquiredsimultaneously. Consequently, a high-quality captured image and distanceinformation can be acquired, and the degree of safety of the driver andthe vehicle can be increased.

In the above-described examples, the solid-state imaging device thatuses electrons as signal charges with the first conductivity type asP-type and the second conductivity type as N-type has been described.The present technology is also applicable to a solid-state imagingdevice that uses holes as signal charges. That is, with the firstconductivity type as N-type and the second conductivity type as P-type,each semiconductor region described above can be formed by asemiconductor region of the opposite conductivity type.

Embodiments of the present technology are not limited to theabove-described embodiment, and various modifications can be madewithout departing from the gist of the present technology.

For example, a form combining all of or part of the embodimentsdescribed above can be used.

It should be noted that the effects described in the present descriptionare merely examples and not limiting. Effects other than those describedin the present description may be included.

Note that the present technology can also take the followingconfigurations.

(1)

A solid-state imaging device including:

a plurality of pixel sets each including color filters of the samecolor, for a plurality of colors, each pixel set including a pluralityof pixels, each pixel including a plurality of photoelectric conversionparts.

(2)

The solid-state imaging device according to (1) described above, inwhich

each pixel includes two photoelectric conversion parts disposedsymmetrically in a vertical direction or a horizontal direction, and

orientations of the photoelectric conversion parts of the pixels are thesame direction at least in each individual pixel set.

(3)

The solid-state imaging device according to (2) described above, inwhich

the orientations of the photoelectric conversion parts of the pixels arethe same direction in all the pixel sets.

(4)

The solid-state imaging device according to (1) described above, inwhich

each pixel includes two photoelectric conversion parts disposedsymmetrically in a vertical direction or a horizontal direction, and

orientations of the photoelectric conversion parts of two of the pixelsarranged in the horizontal direction in each pixel set are the samedirection.

(5)

The solid-state imaging device according to (1) described above, inwhich

each pixel includes two photoelectric conversion parts disposedsymmetrically in a vertical direction or a horizontal direction, and

orientations of the photoelectric conversion parts of two of the pixelsarranged in the horizontal direction in each pixel set are orthogonaldirections.

(6)

The solid-state imaging device according to any one of (1) to (5)described above, in which

the plurality of photoelectric conversion parts of each pixel isisolated from each other by an insulating layer.

(7)

The solid-state imaging device according to any one of (1) to (5)described above, in which

the plurality of photoelectric conversion parts of each pixel isisolated from each other by an impurity layer of a conductivity typeopposite to a conductivity type of the photoelectric conversion parts.

(8)

The solid-state imaging device according to (7) described above, inwhich

the impurity layer forms a potential barrier lower than a potentialbarrier at pixel boundaries.

(9)

The solid-state imaging device according to any one of (1) to (8)described above, in which

a light-shielding film is formed at some of the plurality of pixel sets,the light-shielding film partly shielding all the pixels in each pixelset from light.

(10)

The solid-state imaging device according to any one of (1) to (8)described above, in which

a light-shielding film is formed at some of the plurality of pixel sets,the light-shielding film entirely shielding some of the pixels in eachpixel set from light.

(11)

The solid-state imaging device according to any one of (1) to (10)described above, further including:

a charge holding part that holds charges generated in the photoelectricconversion parts,

the charge holding part adding and outputting charges generated in thephotoelectric conversion parts of the plurality of pixels.

(12)

The solid-state imaging device according to (11) described above, inwhich

the charge holding part adds and outputs charges generated in thephotoelectric conversion parts of all the pixels in each pixel set.

(13)

The solid-state imaging device according to (11) described above, inwhich

the charge holding part adds and outputs charges in the photoelectricconversion parts whose positions in the pixels are the same position, ofthe photoelectric conversion parts of the plurality of pixels includedin each pixel set.

(14)

The solid-state imaging device according to any one of (1) to (13)described above, in which

of the photoelectric conversion parts of the plurality of pixelsincluded in each pixel set, a first photoelectric conversion part and asecond photoelectric conversion part are exposed for different exposuretimes.

(15)

The solid-state imaging device according to (14) described above,further including:

a control unit that performs control to output charges of light receivedby each photoelectric conversion part as a pixel signal,

the control unit outputting a first pixel signal of the firstphotoelectric conversion part exposed for a first exposure time, andoutputting a second pixel signal of the second photoelectric conversionpart exposed for a second exposure time.

(16)

The solid-state imaging device according to any one of (1) to (15)described above, in which

pixel signals generated in the plurality of photoelectric conversionparts of at least some of the plurality of pixels included in each pixelset are output separately.

(17)

The solid-state imaging device according to any one of (1) to (16)described above, in which

of the plurality of pixels included in each pixel set, the photoelectricconversion parts of a first pixel are exposed for a first exposure time,the photoelectric conversion parts of a second pixel are exposed for asecond exposure time shorter than the first exposure time, and pixelsignals generated in the plurality of photoelectric conversion parts ofthe second pixel exposed for the second exposure time are outputseparately.

(18)

The solid-state imaging device according to any one of (1) to (16)described above, in which

of the plurality of pixels included in each pixel set, the photoelectricconversion parts of a first pixel are exposed for a first exposure time,the photoelectric conversion parts of a second pixel are exposed for asecond exposure time shorter than the first exposure time, thephotoelectric conversion parts of a third pixel are exposed for a thirdexposure time shorter than the second exposure time, and pixel signalsgenerated in the plurality of photoelectric conversion parts of thesecond pixel exposed for the second exposure time are output separately.

(19)

The solid-state imaging device according to any one of (1) to (18)described above, in which

the color filters in the pixel sets are arranged in a Bayer array.

(20)

An electronic apparatus including:

a solid-state imaging device including

a plurality of pixel sets each including color filters of the samecolor, for a plurality of colors, each pixel set including a pluralityof pixels, each pixel including a plurality of photoelectric conversionparts.

REFERENCE SIGNS LIST

-   1 Solid-state imaging device-   2 Pixel-   PD Photodiode-   TG Transfer transistor-   3 Pixel array-   5 Column signal processing circuit-   12 Semiconductor substrate-   31, 32 Semiconductor region-   36 Inter-pixel light-shielding film-   37 Color filter-   38 On-chip lens-   51 (51Gr, 51Gb, 51R, 51B) Pixel set-   91 On-chip lens-   101 Insulating layer-   102 Impurity layer-   121 Light-shielding film-   200 Imaging apparatus-   202 Solid-state imaging device

The invention claimed is:
 1. A pixel array circuit comprising: first,second, third, and fourth pixel sets arranged in a 2x2 matrix in a planview, each of the first, second, third and fourth pixel sets includingfour pixels, each of the pixels including two photoelectric conversionparts, wherein the first and fourth pixel sets are configured to producepixel signals corresponding to light in a first range of wavelengths,the second pixel set is configured to produce pixel signalscorresponding to light in a second range of wavelengths different thanthe first range of wavelengths, the third pixel set is configured toproduce pixel signals corresponding to light in a third range ofwavelengths different than the first and second range of wavelengths,each of the photoelectric conversion parts of the four pixels in thefirst pixel set are arranged in a first orientation, each of thephotoelectric conversion parts of the four pixels in the second pixelset are arranged in a second orientation perpendicular to the firstorientation, each of the photoelectric conversion parts of the fourpixels in the third pixel set are arranged in the second orientation,and each of the photoelectric conversion parts of the four pixels in thefourth pixel set are arranged in the first orientation.
 2. The pixelarray circuit according to claim 1, wherein the first range ofwavelengths corresponds to a green color, the second range ofwavelengths corresponds to a red color, and the third range ofwavelengths corresponds to a blue color.
 3. The pixel array circuitaccording to claim 1, wherein the photoelectric conversion parts arephotodiodes.
 4. The pixel array circuit according to claim 1, whereinthe photoelectric conversion parts have a shape with a major axis, themajor axis of the photoelectric conversion parts in the firstorientation extending in a first direction, and the major axis of thephotoelectric conversion parts in the second orientation extending in asecond direction perpendicular to the first direction.
 5. The pixelarray circuit according to claim 1, wherein the first and fourth pixelsets respectively include a first color filter to produce a first colorcorresponding to the first range of wavelengths, the second pixel setincludes a second color filter to produce a second color correspondingto the second range of wavelengths, and the third pixel set includes athird color filter to produce a third color corresponding to the thirdrange of pixel wavelengths.
 6. The pixel array circuit according toclaim 1, wherein the photoelectric conversion parts are isolated fromeach other by an insulating layer.
 7. The pixel array circuit accordingto claim 1, further comprising: a charge holding part that holds chargesgenerated in the photoelectric conversion parts, the charge holding partadding and outputting charges generated in the photoelectric conversionparts.
 8. The pixel array circuit according to claim 7, wherein thecharge holding part adds and outputs charges generated in thephotoelectric conversion parts of all the pixels in each pixel set. 9.An imaging device comprising: a pixel array including first, second,third, and fourth pixel sets arranged in a 2x2 matrix in a plan view,each of the first, second, third and fourth pixel sets including fourpixels, each of the pixels including two photoelectric conversion parts,wherein the first and fourth pixel sets are configured to produce pixelsignals corresponding to light in a first range of wavelengths, thesecond pixel set is configured to produce pixel signals corresponding tolight in a second range of wavelengths different than the first range ofwavelengths, the third pixel set is configured to produce pixel signalscorresponding to light in a third range of wavelengths different thanthe first and second range of wavelengths, each of the photoelectricconversion parts of the four pixels in the first pixel set are arrangedin a first orientation, each of the photoelectric conversion parts ofthe four pixels in the second pixel set are arranged in a secondorientation perpendicular to the first orientation, each of thephotoelectric conversion parts of the four pixels in the third pixel setare arranged in the second orientation, and each of the photoelectricconversion parts of the four pixels in the fourth pixel set are arrangedin the first orientation.
 10. The imaging device according to claim 9,wherein the first range of wavelengths corresponds to a green color, thesecond range of wavelengths corresponds to a red color, and the thirdrange of wavelengths corresponds to a blue color.
 11. The imaging deviceaccording to claim 9, wherein the photoelectric conversion parts arephotodiodes.
 12. The imaging device according to claim 9, wherein thephotoelectric conversion parts have a shape with a major axis, the majoraxis of the photoelectric conversion parts in the first orientationextending in a first direction, and the major axis of the photoelectricconversion parts in the second orientation extending in a seconddirection perpendicular to the first direction.
 13. The imaging deviceaccording to claim 9, wherein the first and fourth pixel setsrespectively include a first color filter to produce a first colorcorresponding to the first range of wavelengths, the second pixel setincludes a second color filter to produce a second color correspondingto the second range of wavelengths, and the third pixel set includes athird color filter to produce a third color corresponding to the thirdrange of pixel wavelengths.
 14. The imaging device according to claim 9,wherein the photoelectric conversion parts are isolated from each otherby an insulating layer.
 15. The imaging device according to claim 9,further comprising: a charge holding part that holds charges generatedin the photoelectric conversion parts, the charge holding part addingand outputting charges generated in the photoelectric conversion parts.16. The imaging device according to claim 15, wherein the charge holdingpart adds and outputs charges generated in the photoelectric conversionparts of all the pixels in each pixel set.
 17. An electronic apparatuscomprising: a pixel array; and at least one control circuit configuredto drive the pixel array, the pixel array including first, second,third, and fourth pixel sets arranged in a 2x2 matrix in a plan view,each of the first, second, third and fourth pixel sets including fourpixels, each of the pixels including two photoelectric conversion parts,wherein the first and fourth pixel sets are configured to produce pixelsignals corresponding to light in a first range of wavelengths, thesecond pixel set is configured to produce pixel signals corresponding tolight in a second range of wavelengths different than the first range ofwavelengths, the third pixel set is configured to produce pixel signalscorresponding to light in a third range of wavelengths different thanthe first and second range of wavelengths, each of the photoelectricconversion parts of the four pixels in the first pixel set are arrangedin a first orientation, each of the photoelectric conversion parts ofthe four pixels in the second pixel set are arranged in a secondorientation perpendicular to the first orientation, each of thephotoelectric conversion parts of the four pixels in the third pixel setare arranged in the second orientation, and each of the photoelectricconversion parts of the four pixels in the fourth pixel set are arrangedin the first orientation.
 18. The electronic apparatus according toclaim 17, wherein the first range of wavelengths corresponds to a greencolor, the second range of wavelengths corresponds to a red color, andthe third range of wavelengths corresponds to a blue color.
 19. Theelectronic apparatus according to claim 17, wherein the photoelectricconversion parts are photodiodes.
 20. The electronic apparatus accordingto claim 17, wherein the photoelectric conversion parts have a shapewith a major axis, the major axis of the photoelectric conversion partsin the first orientation extending in a first direction, and the majoraxis of the photoelectric conversion parts in the second orientationextending in a second direction perpendicular to the first direction.